Definition - The agreement of words in number, person, gender, etc.

Example -
Bob went home. He went to his own home.
(To be in concord, the pronouns He and him must both be in the third person).

Etymology -
The term derives from the Latin concordia, agreement or union; it literally means "hearts together" (from com-, together + cor, heart).

Oxford English Dictionary -
Its first citation is from 1530:
"The latines have the concordes of grammar."
(Jehan Palsgrave, Lesclarcissement de la langue françoyse, Introd. 38 )

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