- similar or alike in every way: The two cars are identical except for their license plates.
- being the very same; selfsame: This is the identical room we stayed in last year.
- agreeing exactly: identical opinions.
- Also called: numerically identical being one and the same individualCicero and Tully are identical
- Also called: quantitatively identical exactly alike, equal, or agreeing
- designating either or both of a pair of twins of the same sex who developed from a single fertilized ovum that split into twoCompare fraternal (def. 3)
1610s, as a term in logic, from Medieval Latin identicus “the same,” from Late Latin identitas “identity, sameness,” ultimately from comb. form of Latin idem “the same” (from id “it, that one;” see id) + demonstrative suffix -dem. General sense of “being the same or very similar” is from 1630s. Replaced Middle English idemptical (late 15c.), from Medieval Latin idemptitas “identity,” from Latin idem. Related: Identically.
- Exactly equal and alike.
- Of or relating to a twin or twins developed from the same fertilized ovum and having the same genetic makeup and closely similar appearance; monozygotic.