Definition - A systematic presentation of the different forms a verb can take with respect to voice, mood, or tense, etc.

Example -

A conjugation of the verb "write."
A conjugation of the verb "write."

Etymology -
The term derives from the Latin conjugare, to join together, which was a translation of a Greek term that denoted a table showing the series of verb's conjugate forms.

Oxford English Dictionary -
Its first citation in this sense is from 1530:
"Conjugation is the dyvers alteryng of the last ende of a theme, by reason of these thre accidentes, mode, tens and declination personall."
( Jehan Palsgrave, Lesclarcissement de la langue françoyse, Introduction 31)

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