Incapable

google

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late 16th century: from French, or from late Latin incapabilis, from in- ‘not’ + capabilis (see capable).

wiktionary

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Borrowed from Middle French incapable, in- +‎ capable

etymonline

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incapable (adj.)

"not capable," 1590s, from French incapable (16c.) and directly from Medieval Latin incapabilis "incapable," from in- "not" (see in- (1)) + capabilis "receptive; able to grasp or hold" (see capable). Related: Incapably; incapability.