an apple a day
see apple a day.
When To Use “A,” “An,” And “The”Articles are words that make it clear whether a noun refers to something specific or something general. The English language has only three articles: a, an, and the. This stanza from Emily Dickinson’s poem “A Bird Came Down the Walk” demonstrates the use of all three: A Bird came down the Walk— He did not know I saw— He bit an Angleworm in halves And …
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.