An

UK: /ˈæn/

US: /ən; when stressed æn/

US: 'an': (ən; when stressed an); 'An': (än)

Collins Concise English Dictionary © HarperCollins Publishers::

An / ɑːn/ noun

1. the Sumerian sky god
   Babylonian counterpart: Anu

WordReference Random House Learner's Dictionary of American English © 2025

an¹ /ən; when stressed æn/   indefinite article. 

1. Pronouns the form of a used before an initial vowel sound:
   an arch, an honor, an hourly wage.

Usage

Sometimes, esp. in British English, an is used before an initial h if the h is silent or weakly pronounced and the syllable is unstressed: "an hisˈtorian''; "an hisˈtoric event''.

an-¹ ,

1. prefix.  an- is attached to roots or stems beginning with a vowel or h, and means "not;
   without;
   lacking'':
   anaerobic (= without oxygen); anonymous (= without name).
   Compare a-².

-an¹ ,suffix. -an has the general meaning "of, pertaining to, having qualities of''.

1. It is used to form adjectives and nouns from names of places or people, with the meanings:
   • being connected with a place: Chicago + -an → Chicagoan;
     
   • having membership in a group of: Episcopal + -(i)an → Episcopalian;
     
2. It is used to form adjectives with the meaning "of or like (someone);
   supporter or believer of'': Christ + -(i)an → Christian;
   Freud + -(i)an → Freudian (= supporter of or believer in the theories of Sigmund Freud).
3. It is used to form nouns from words ending in -ic or -y, with the meaning "one who works with '': electric + -(i)an → electrician;
   comedy + -an → comedian.

WordReference Random House Unabridged Dictionary of American English © 2025

an¹  (ən; when stressed an), indefinite article.

1. Pronouns the form of a before an initial vowel sound (an arch;
   an honor) and sometimes, esp. in British English, before an initial unstressed syllable beginning with a silent or weakly pronounced h:
   an historian.

• bef. 950; Middle English; Old English ān one in a weakened sense

Usage

See a ¹.

an²  (ən; when stressed an), conj. 

1. [Pron. Spelling.] and.
2. [Archaic.] if.

Also, an', 'n, 'n'. 

• Middle English, unstressed phonetic variant of and 1125–75

An  (än), n. 

1. Chemistry, Eastern Religions the Sumerian god of heaven: the counterpart of the Akkadian Anu.

an-¹ ,

1. a prefix occurring before stems beginning with a vowel or h in loanwords from Greek, where it means "not,'' "without,'' "lacking'' (anarchy;
   anecdote);
   used in the formation of compound words:
   anelectric.
   Also, before a consonant, a-. 

• Greek. See a-⁶, in-³, un-¹

an-² ,

1. var. of ad- before
   n: announce.

an-³ ,

1. var. of ana- before a vowel:
   anion.

-an ,

1. a suffix occurring originally in adjectives borrowed from Latin, formed from nouns denoting places (Roman;
   urban) or persons (Augustan), and now productively forming English adjectives by extension of the Latin pattern. Attached to geographic names, it denotes provenance or membership (American;
   Chicagoan;
   Tibetan), the latter sense now extended to membership in social classes, religious denominations, etc., in adjectives formed from various kinds of noun bases (Episcopalian;
   pedestrian;
   Puritan;
   Republican) and membership in zoological taxa (acanthocephalan;
   crustacean). Attached to personal names, it has the additional senses "contemporary with'' (Elizabethan;
   Jacobean) or "proponent of '' (Hegelian;
   Freudian) the person specified by the noun base. The suffix -an, and its variant -ian, also occurs in a set of personal nouns, mainly loanwords from French, denoting one who engages in, practices, or works with the referent of the base noun (comedian;
   grammarian;
   historian;
   theologian);
   this usage is esp. productive with nouns ending in -ic (electrician;
   logician;
   technician). See -ian for relative distribution with that suffix. Cf. -enne, -ean, -arian, -ician.

• Latin
• Old French
• Latin -ānus, -āna, -ānum; in some words replacing -ain, -en
• Middle English

AN ,

1. Language Varieties Anglo-Norman.

Also, A.-N. 
An ,[Symbol, Chem.]

1. actinon.

an. ,

1. in the year.

• Latin annō

A.N. ,

1. Language Varieties Anglo-Norman.
2. Associate in Nursing.

Collins Concise English Dictionary © HarperCollins Publishers::

AN abbreviation

1. Anglo-Norman

Collins Concise English Dictionary © HarperCollins Publishers::

an / æn (unstressed) ən/ determiner

1. a form of the indefinite article used before an initial vowel sound: an old car, an elf, an honour

Etymology: Old English ān oneUSAGE
An was formerly often used before words that begin with h and are unstressed on the first syllable: an hotel; an historic meeting. Sometimes the initial h was not pronounced. This usage is now becoming obsolete

an, an' / æn (unstressed) ən/ conjunction

1. (subordinating)
   an obsolete or dialect word for if
   See and9