Antonyms of adj inexcusable

2 senses of inexcusable

Sense 1
inexcusable (vs. excusable) -- (without excuse or justification)

excusable (vs. inexcusable) -- (capable of being overlooked)
        => justifiable -- (capable of being justified)

Sense 2
inexcusable, unforgivable -- (not excusable)

INDIRECT (VIA unpardonable) -> pardonable -- (admitting of being pardoned)

Similarity of adj inexcusable

2 senses of inexcusable

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

Sense 2
inexcusable, unforgivable -- (not excusable)
       => unpardonable (vs. pardonable) -- (not admitting of pardon; "unpardonable behavior")