best friend

plural best friends

Definition of best friend

1 : a person's closest and dearest friend She's my best friend. We have been best friends since high school.
2 : a person's most desirable or valuable possession or resource Diamonds may be a girl's best friend, but gold is more affordable.— William Giese Lycra-cotton leggings and tunic tops are the pregnant woman's best friend, sartorially speaking.— Anne Reeks When cops bang on the door, the toilet is a drug dealer's best friend.— Frederick Kaufman — see also man's best friend

First Known Use of best friend

13th century, in the meaning defined at sense 1

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The first known use of best friend was in the 13th century

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Dictionary Entries Near best friend

best foot

best friend

best girl

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Cite this Entry

“Best friend.” Dictionary, Merriam-Webster, Accessed 17 Oct. 2021.

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