a vs. an

In English writing, the indefinite article 'a' or 'an' is used before a nonspecific 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
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rID: 30716
Synonyms or Alternate Spellings:

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