Synonyms for Unendurable:

adj.

•unbearable (adjective)
insupportable, unsufferable, insufferable, intolerable, impossible, unsupportable.

n.

agonising, burning, angry, crippling, achy, acute, chapped, chronic, agonizing, bad. insupportable, unsufferable, insufferable, pain, impossible, unsupportable. •excessive (noun)
extreme, insupportable.
•unendurable (noun)
intolerable, unbearable.

Other synonyms:

unsufferable, unsupportable. insupportable. impossible. •unbearable
insufferable, unbearable.
•Other relevant words:
impossible, insufferable, extreme, intolerable, acute, insupportable, unsufferable, agonizing, unsupportable.

Usage examples for unendurable

1. At eighteen she would be unendurable – Together by Robert Herrick (1868-1938)

2. It puts her in an unendurable position to have to defend such a person. – The Title Market by Emily Post