1. Not capable of being surmounted or overcome
   "insurmountable disadvantages"
   - unsurmountable 
2. Impossible to surmount
   - insuperable

See also: impossible, insuperable, unconquerable

Antonym: surmountable

• Eupatorium maculatum
• Eupatorium perfoliatum
• Eupatorium purpureum
• Eupatorium rugosum
• eupeptic
• Euphagus
• Euphagus carilonus
• Euphausia pacifica
• Euphausiacea
• euphemise
• euphemism
• euphemistic
• euphemistically
• euphemize
• euphonic
• euphonical
• euphonious
• euphonium
• euphonous
• euphony
• Euphorbia
• Euphorbia amygdaloides
• Euphorbia antisyphilitica
• Euphorbia caput-medusae
• Euphorbia corollata