Antonyms of adj insupportable

1 sense of insupportable

Sense 1
indefensible, insupportable, unjustifiable, unwarrantable, unwarranted -- (incapable of being justified or explained)

INDIRECT (VIA inexcusable) -> excusable -- (capable of being overlooked)

Similarity of adj insupportable

1 sense of insupportable

Sense 1
indefensible, insupportable, unjustifiable, unwarrantable, unwarranted -- (incapable of being justified or explained)
       => inexcusable (vs. excusable) -- (without excuse or justification)