An

[A-S. an, ane, one, Goth. áins, Ger. ein, D. een, Sw. & Dan. en, Lat. unus.] This word is properly an adjective, but is commonly called the indefinite article. It is used before nouns of the singular number only, and signifies one, or any, but somewhat less emphatically. In such expressions as “twice an hour,” “once an age,” “a shilling an ounce,” it has a distributive force, and is equivalent to each, every.

An is used before a word beginning with a vowel sound; as, an enemy, an hour. It is also used before h sounded, when the accent of the word falls on any syllable except the first; as, an historian, an horticulturist, an humanitarian. It was anciently used before all consonants.

conj. [The imperative of the A-S. verb unnan, root ann, to grant, to give. Cf. If.] If;—a word used by old English authors. Nay, an thou dalliest, then I am thy foe. B. Jonson. Fool, fool, fool! catch me an thou canst. Ford. An if, for if, or for as if, though an incorrect expression, sometimes occurs.