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first come, first served

Those who are first to arrive will be the first to be waited on.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Idioms and Phrases with first come, first served

first come, first served

Those who precede others will have their needs attended to earliest, as in So many people showed up that we may not have enough food to go around, so let it be “first come, first served.” The idea is very old, but the first recorded use of this precise phrase was in 1545. Also see early bird catches the worm.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.