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an
/ən/
indefinite article
She bought an apple.
Used before a singular noun starting with a vowel sound.
general
Used before a singular noun starting with a vowel sound or silent 'h'.
He has an umbrella.
Used before 'umbrella' (starts with 'u' sound).
She is an honest person.
Used before 'honest' (starts with 'o' sound).
In British English, 'an' is also used before words starting with silent 'h' (e.g., 'an hour').
Collocations
an examplea single instance of somethingan ideaa thought or suggestionan opportunitya chance to do something
Synonyms
Pro Tip
Vowel Sound Rule
Use 'an' before words that start with a vowel sound, not just the letter 'a' (e.g., 'an hour' because 'hour' starts with a silent 'h').
Gold Rule
Indefinite Article
'An' is used to refer to one of many, without specifying which one.
Word Origin
From Middle English 'an', from Old English 'ān' (one).
Usage Notes
Use 'an' before words starting with vowel sounds (a, e, i, o, u) or silent 'h'. In American English, 'a' is often used before words starting with silent 'h' (e.g., 'a historic event').
English Dictionary