The definition of invincible is someone or something that cannot be harmed or that is too powerful to be destroyed.(adjective)
A superhero who cannot be killed is an example of someone who would be described as invincible.
See invincible in Webster's New World College Dictionary
Origin: ME invyncyble < MFr invincible < L invincibilis: see in- & vincible
See invincible in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French
Origin: , from Latin invincibilis
Origin: : in-, not; see in-1
Origin: + vincibilis, conquerable; see vincible.
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