headlong

UK: /ˈhɛdlɒŋ/ US: /ˈhɛdˌlɔŋ, -ˌlɑŋ/ ,(hed′lông′, -long′)

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

head•long /ˈhɛdˌlɔŋ, -ˌlɑŋ/   adv. 

1. with the head going first;
   headfirst:
   to plunge headlong into the water.
2. without delay;
   hastily;
   rashly:
   to rush headlong into marriage.

adj. 

3. hasty:
   a headlong flight.
4. done or going with the head foremost:
   a headlong dive.

WordReference Random House Unabridged Dictionary of American English © 2026

head•long  (hed′lông′, -long′), adv. 

1. with the head foremost;
   headfirst:
   to plunge headlong into the water.
2. without delay;
   hastily:
   to plunge headlong into work.
3. without deliberation;
   rashly:
   to rush headlong into battle.

adj. 

4. undertaken quickly and suddenly;
   made precipitately;
   hasty:
   a headlong flight.
5. rash;
   impetuous:
   a headlong denunciation.
6. done or going with the head foremost:
   a headlong dive into the pool.

• Middle English hedlong, earlier hedling. See head, -ling² 1350–1400

head′long′ness, n. 

Collins Concise English Dictionary © HarperCollins Publishers::

headlong / ˈhɛdˌlɒŋ/ adverb , adjective

1. with the head foremost; headfirst
2. with great haste

adjective

1. (of slopes, etc) very steep; precipitous