To help, aid, or assist someone or something.
From Latin adjuvāre (to help, aid), composed of ad- (to) + juvāre (to help). This verb form is extremely rare in modern English.
This verb is so obscure that even most dictionaries skip it, but it's the original verb form from which all the other 'adjuv-' words sprung—it's the root that gave birth to adjuvant, adjuvation, and all the rest.
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