Et is Latin as is defined as "and."(conjunction)
An example of the use of et as a conjunction is in the saying "et. all" which means and others.
See et in Webster's New World College Dictionary
Origin: Fr < L
Origin: ME -et < OFr -et, masc., -ete (Fr -ette), fem. < LL -itus, -ita
See et in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French
Origin: , from Vulgar Latin *-ittum.
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