INSURMOUNTABLE

insuperable, insurmountable

(adjective) impossible to surmount

insurmountable, unsurmountable

(adjective) not capable of being surmounted or overcome; “insurmountable disadvantages”

Source: WordNet® 3.1

Etymology

Adjective

insurmountable (comparative more insurmountable, superlative most insurmountable)

Incapable of being passed over, surmounted, or overcome; insuperable

Antonyms

• surmountable

Source: Wiktionary

In`sur*mount"a*ble, a. Etym: [Pref. in- not + surmountable: cf. F. insurmountable.]

Definition: Incapable of being passed over, surmounted, or overcome; insuperable; as, insurmountable difficulty or obstacle. Locke. Hope thinks nothing difficult; despair tells us that difficulty is insurmountable. I. Watts.

Syn.

– Insuperable; impassable; invincible.

Source: Webster’s Unabridged Dictionary 1913 Edition