a vs an
Citation, DOI, disclosures and article data
Citation:
Luijkx T, Bell D, Glick Y, a vs an. Reference article, Radiopaedia.org (Accessed on 15 Mar 2025) https://doi.org/10.53347/rID-30716
Permalink:
rID:
30716
Article created:
30 Aug 2014,
Tim Luijkx
Disclosures:
At the time the article was created Tim Luijkx had no recorded disclosures.
View Tim Luijkx's current disclosures
Last revised:
Disclosures:
At the time the article was last revised Daniel J Bell had no recorded disclosures.
View Daniel J Bell's current disclosures
Revisions:
6 times, by
3 contributors -
see full revision history and disclosures
Synonyms:
- indefinite article
- indefinite articles
In English writing, the indefinite article 'a' or 'an' is used before a non-specific noun, as opposed to 'the' for a definite article. For instance, 'a house' does not reference one house specifically, whereas 'the house' refers to a particular house.
The article 'a' precedes a word that starts with a consonant, while 'an' precedes a word that starts with a vowel sound.
Examples
- a bone
- an arm
- an MRI scan (M is pronounced 'em')
- a ureter (the 'u' is pronounced 'you')
- a hair
- an hour (pronounced 'our'; the 'h' is silent)
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