'Unsurmountable' definitions:

Definition of 'unsurmountable'

From: WordNet
adjective
Not capable of being surmounted or overcome; "insurmountable disadvantages" [syn: insurmountable, unsurmountable] [ant: surmountable]
adjective
Incapable of being surmounted or climbed [syn: unsurmountable, unclimbable]

Definition of 'Unsurmountable'

From: GCIDE
  • Unsurmountable \Un`sur*mount"a*ble\, a. Insurmountable. --Locke. [1913 Webster]