lock horns

WordReference Random House Learner's Dictionary of American English © 2026

horn /hɔrn/   n. 

1. Zoology [countable] one of the hard, permanent, hollow, and usually paired growths that stick out from the heads of cows, goats, sheep, etc.
2. Zoology [countable] a similar growth, as an antler.
3. Zoology the hard substance of which horn growths are made:
   [uncountable] a handle made of horn.
4. Music and Dance [countable] a wind instrument in music, as a trumpet.
5. Automotive an instrument for sounding a warning signal:
   [countable] an automobile horn.
6. Telecommunications, Slang Terms [ count;
   usually: the + ~][Slang.] a telephone:
   been on the horn all morning.

v. 

7. horn in, [Informal.] to intrude: [no object]
   He was always horning in when I tried to talk to her.
   [~ + in + on + object]
   He was horning in on our conversation.

adj. [before a noun]

8. made of horn:
   a horn handle.

Idioms

9. Idioms blow or toot one's own horn, to boast about oneself.
10. Idioms on the horns of a dilemma, facing and forced to choose between two equally difficult choices.

horned, adj. 

: a great horned owl.

horn•less, adj. 

WordReference Random House Learner's Dictionary of American English © 2026

lock¹ /lɑk/   n. 

[countable]
1. Building a device for keeping a door, gate, lid, drawer, or the like securely closed or fastened, made up of a bolt or system of bolts moved by a key, dial, etc.
2. (in a firearm) the mechanism that explodes the charge.
3. Civil Engineering an enclosed chamber in a canal, dam, etc., with gates at each end, for raising or lowering vessels from one level to another by increasing or decreasing water in the chamber.
4. complete and unchallenged control or an unbreakable hold:
   to have a lock on the senatorial nomination.
5. Slang Terms a sure thing:
   The team is a lock to win the championship.

v. 

6. to (cause a door, window, building, etc., to) become fastened or made secure by the operation of a lock or locks: [~ + object]
   I locked the car doors.
   [no object]
   The car doors lock automatically.
7. to shut in a place by or as if by means of a lock:
   [~ + object] We locked the hamster in its cage.
8. to (cause to) become fastened, fixed, interlocked, or jammed by or as if by a lock: [~ + object]
   to lock the steering wheel on a car to prevent theft.
   [no object]
   The gears locked into place.
9. to unite firmly by linking:
   [~ + object] to lock arms.
10. to hold fast in an embrace:
    [~ + object] She locked him in her arms.
11. lock in:
    • to (cause to) be aimed at (a target or goal) and be unable to change: [~ + in + object]
      The pilot locked in his target.
      [~ + object + in]
      The pilot locked it in and fired.
      [~ + in + on + object]
      The missiles locked in on the target.
    • to put into a place, room, etc., and lock its doors: [~ + object + in]
      They locked him in with the other prisoners.
      [~ + in + object]
      The guard locked in the prisoners every night.
12. lock out:
    • [~ + object + out] to keep out by or as if by a lock:
      I was locked out of my car.
    • to subject (employees) to a lockout: [~ + out + object]
      The boss locked out the striking employees.
      [~ + object + out]
      to lock them out if they don't negotiate.
13. lock up:
    • to imprison for a crime: [~ + object + up]
      took him away and locked him up.
      [~ + up + object]
      locking up criminals.
    • to make secure with a lock: [~ + up + object]
      locked up the money in his safe.
      [~ + object + up]
      locked the money up in his safe.
      [no object]
      The watchman locked up for the night.
    • to fasten or fix firmly, as by engaging parts: [no object]
      The car's brakes locked up.
      [~ + up + object]
      Slamming on the brakes will lock up your wheels.
      [~ + object + up]
      Something locked the gears up.

Idioms

14. Idioms lock horns, [~ (+ with + object)] to come into conflict;
    clash:
    They locked horns with their critics.
15. Idioms lock, stock, and barrel, with every part or item included;
    completely:
    He'll sue you lock, stock, and barrel.
16. Idioms under lock and key, securely locked up:
    to keep important papers under lock and key.

lock² /lɑk/   n. [countable]

1. a tuft or ringlet of hair.
2. locks, [plural] the hair of the head:
   golden locks.

WordReference Random House Unabridged Dictionary of American English © 2026

horn  (hôrn), n. 

1. Zoology one of the bony, permanent, hollow paired growths, often curved and pointed, that project from the upper part of the head of certain ungulate mammals, as cattle, sheep, goats, or antelopes.
2. Zoology a similar growth, sometimes of hair, as the median horn or horns on the snout of the rhinoceros, or the tusk of the narwhal.
3. Zoology antler.
4. Zoology a process projecting from the head of an animal and suggestive of such a growth, as a feeler, tentacle, or crest.
5. Zoology the bony substance of which such animal growths are composed.
6. Zoology, Anatomy any similar substance, as that forming tortoise shell, hoofs, nails, or corns.
7. an article made of the material of an animal horn or like substance, as a thimble, spoon, or shoehorn.
8. any projection or extremity resembling the horn of an animal.
9. something resembling or suggesting an animal horn:
   a drinking horn.
10. a part resembling an animal horn attributed to deities, demons, etc.:
    the devil's horn.
11. Usually, horns. the imaginary projections on a cuckold's brow.
12. Music and Dance
    • a wind instrument, originally formed from the hollow horn of an animal but now usually made of brass or other metal or plastic.
    • See French horn. 
13. Music and Dance something used as or resembling such a wind instrument.
14. Music and Dance [Slang.] a trumpet.
15. Automotive an instrument for sounding a warning signal:
    an automobile horn.
16. Aeronautics any of certain short, armlike levers on the control surfaces of an airplane.
17. [Radio.]
    • Radio and Television a tube of varying cross section used in some loudspeakers to couple the diaphragm to the sound-transmitting space.
    • Slang Terms a loudspeaker.
18. Telecommunications, Slang Terms [Slang.] a telephone or radiotelephone:
    I've been on the horn all morning.
19. the high protuberant part at the front and top of certain saddles;
    a pommel, esp. a high one.
20. Building [Carpentry.] (in a door or window frame) that part of a jamb extending above the head.
21. Astronomy one of the curved extremities of a crescent, esp. of the crescent moon.
22. Geography a crescent-shaped tract of land.
23. Geography a pyramidal mountain peak, esp. one having concave faces carved by glaciation.
24. a symbol of power or strength, as in the Bible:
    a horn of salvation.
25. each of the alternatives of a dilemma.
26. Building the narrow, more pointed part of an anvil.
27. Metallurgy a projection at the side of the end of a rolled sheet or strip, caused by unevenness of the roll due to wear.
28. Time [Horol.] (in a lever escapement) either of the two prongs at the end of the lever fork guarding against overbanking when the guard pin is in the crescent.
29. Idioms blow ( or toot) one's own horn, [Informal.] to publicize or boast about one's abilities or achievements:
    He's a bright fellow, but likes to blow his own horn too much.
30. Idioms draw or pull in one's horns, to restrain oneself or become less belligerent;
    retreat:
    Since he lost so much gambling, he's drawn in his horns a bit.
31. Idioms lock horns, to conflict, quarrel, or disagree:
    The administration and the staff locked horns over the proposed measures.
32. Idioms on the horns of a dilemma, confronted with two equally disagreeable choices.

v.t. 

33. to cuckold.
34. to butt or gore with the horns.
35. Nautical, Naval Terms [Shipbuilding.] to set up (a frame or bulkhead of a vessel being built) at a proper angle to the keel with due regard to the inclination of the keel on the ways;
    plumb.
36. horn in, [Informal.] to thrust oneself forward obtrusively;
    intrude or interrupt:
    Every time we try to have a private conversation, the boss horns in.

adj. 

37. made of horn.

• bef. 900; Middle English horn(e) (noun, nominal), Old English horn; cognate with Dutch horen, Old Norse, Danish, Swedish horn, German Horn, Gothic haurn, Latin cornu cornu, Irish, Welsh corn; akin to Greek kéras horn (see cerat-)

horn′ish, adj. 
horn′less, adj. 
horn′less•ness, n. 
horn′like′, adj. 

Horn  (hôrn), n. 

1. Place Names Cape. See Cape Horn. 

WordReference Random House Unabridged Dictionary of American English © 2026

lock¹  (lok), n. 

1. Building a device for securing a door, gate, lid, drawer, or the like in position when closed, consisting of a bolt or system of bolts propelled and withdrawn by a mechanism operated by a key, dial, etc.
2. Building a contrivance for fastening or securing something.
3. (in a firearm)
   • the mechanism that explodes the charge;
     gunlock.
   • safety (def. 4).
4. Building any device or part for stopping temporarily the motion of a mechanism.
5. Civil Engineering an enclosed chamber in a canal, dam, etc., with gates at each end, for raising or lowering vessels from one level to another by admitting or releasing water.
6. an air lock or decompression chamber.
7. complete and unchallenged control;
   an unbreakable hold:
   The congresswoman has a lock on the senatorial nomination.
8. Slang Terms someone or something certain of success;
   sure thing:
   He's a lock to win the championship.
9. Sport [Wrestling.] any of various holds, esp. a hold secured on the arm, leg, or head:
   leg lock.
10. Time [Horol.] (in an escapement) the overlap between a tooth of an escape wheel and the surface of the pallet locking it.
11. Metallurgy a projection or recession in the mating face of a forging die.
12. Idioms lock, stock, and barrel, completely;
    entirely;
    including every part, item, or facet, no matter how small or insignificant:
    We bought the whole business, lock, stock, and barrel.
13. Idioms under lock and key, securely locked up:
    The documents were under lock and key.

v.t. 

14. Building to fasten or secure (a door, window, building, etc.) by the operation of a lock or locks.
15. Building to shut in a place fastened by a lock or locks, as for security or restraint.
16. Building to make fast or immovable by or as if by a lock:
    He locked the steering wheel on his car.
17. Building to make fast or immovable, as by engaging parts:
    to lock the wheels of a wagon.
18. to join or unite firmly by interlinking or intertwining:
    to lock arms.
19. to hold fast in an embrace:
    She was locked in his arms.
20. Civil Engineering, Nautical, Naval Terms to move (a ship) by means of a lock or locks, as in a canal (often fol. by through, in, out, down, or up).
21. Civil Engineering to furnish with locks, as a canal.

v.i. 

22. to become locked:
    This door locks with a key.
23. Building to become fastened, fixed, or interlocked:
    gears that lock into place.
24. to go or pass by means of a lock or locks, as a vessel.
25. Civil Engineering to construct locks in waterways.
26. Idioms lock horns, to come into conflict;
    clash:
    to lock horns with a political opponent.
27. lock in:
    • to commit unalterably:
      to lock in the nomination of the party's candidates.
    • (of an investor) to be unable or unwilling to sell or shift securities.
28. Civil Engineering lock off, to enclose (a waterway) with a lock.
29. Electronics lock on, to track or follow a target or object automatically by radar or other electronic means.
30. lock out:
    • to keep out by or as if by a lock.
    • to subject (employees) to a lockout.
31. lock up:
    • to imprison for a crime.
    • Printing to make (type) immovable in a chase by securing the quoins.
    • to fasten or secure with a lock or locks.
    • to lock the doors of a house, automobile, etc.
    • to fasten or fix firmly, as by engaging parts.

• bef. 900; Middle English; Old English loc fastening, bar; cognate with Middle Low German lok, Old High German loh, Old Norse lok a cover, lid, Gothic -luk in usluk opening; akin to Old English lūcan to shut

lock′less, adj. 

lock²  (lok), n. 

1. a tress, curl, or ringlet of hair.
2. locks:
   • the hair of the head.
   • short wool of inferior quality, as that obtained in small clumps from the legs.
3. a small tuft or portion of wool, cotton, flax, etc.

• Middle English locke, Old English locc lock of hair, cognate with Old Norse lokkr, Dutch lok curl, German Locke bef. 900

Collins Concise English Dictionary © HarperCollins Publishers::

lock / lɒk/ noun

1. a device fitted to a gate, door, drawer, lid, etc, to keep it firmly closed and often to prevent access by unauthorized persons
2. a similar device attached to a machine, vehicle, etc, to prevent use by unauthorized persons: a steering lock
3. a section of a canal or river that may be closed off by gates to control the water level and the raising and lowering of vessels that pass through it
4. (as modifier): a lock gate
5. the jamming, fastening, or locking together of parts
6. the extent to which a vehicle's front wheels will turn to the right or left: this car has a good lock
7. a mechanism that detonates the charge of a gun
8. a person or thing that is certain to win or to succeed: she is a lock for the Academy Award
9. lock, stock, and barrel ⇒ completely; entirely
10. any wrestling hold in which a wrestler seizes a part of an opponent's body and twists it or otherwise exerts pressure upon it
11. Also called: lock forward either of two players who make up the second line of the scrum and apply weight to the forwards in the front line
12. a gas bubble in a hydraulic system or a liquid bubble in a pneumatic system that stops or interferes with the fluid flow in a pipe, capillary, etc: an air lock

verb

1. to fasten (a door, gate, etc) or (of a door, etc) to become fastened with a lock, bolt, etc, so as to prevent entry or exit
2. (transitive) to secure (a building) by locking all doors, windows, etc
3. to fix or become fixed together securely or inextricably
4. to become or cause to become rigid or immovable: the front wheels of the car locked
5. (when tr, often passive) to clasp or entangle (someone or each other) in a struggle or embrace
6. (transitive) to furnish (a canal) with locks
7. (transitive) to move (a vessel) through a system of locks
8. lock horns ⇒ (esp of two equally matched opponents) to become engaged in argument or battle
9. lock the stable door after the horse has bolted, lock the stable door after the horse has been stolen ⇒ to take precautions after harm has been done

Etymology: Old English loc; related to Old Norse lok

ˈlockable adjective

lock / lɒk/ noun

1. a strand, curl, or cluster of hair
2. a tuft or wisp of wool, cotton, etc
3. (plural) hair, esp when curly or fine

Etymology: Old English loc; related to Old Frisian lok, Old Norse lokkr lock of wool