Synonyms of the word 
UNTENABLE → INDEFENSIBLE - UNREASONABLE
untenable
- adj. Not able to be held, as of an opinion or position; unholdable, indefensible.
indefensible
- adj. Not defensible; not capable of being defended; vulnerable.
- adj. Incapable of being justified or excused; inexcusable; unpardonable.
- adj. Incapable of being explained; untenable; insupportable; invalid.
unreasonable
- adj. Not reasonable.
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