- not endurable; unbearable; insufferable: insupportable pain.
- incapable of support or justification, as by evidence or collected facts: an insupportable accusation.
- incapable of being endured; intolerable; insufferable
- incapable of being supported or justified; indefensible
1520s, from French insupportable (14c.) or directly from Late Latin insupportabilis, from in- “not” (see (1)) + Latin supportare “to carry” (see ).