1. No longer in existence; lost or especially having died out leaving no living representatives
   - extinct 
2. No longer existing or inaccessible through loss or destruction
   "its nonextant original was written on vellum"

See also: dead, nonexistent

• nonlinear distortion
• nonlinear system
• nonlinguistic
• nonliteral
• nonliterary
• nonliterate
• nonliving
• nonmagnetic
• nonmalignant neoplasm
• Illecebrum
• Illecebrum verticullatum
• illegal
• illegal immegrant
• illegal possession
• illegalise
• illegality
• illegalize
• illegally
• illegibility
• illegible
• illegibly
• illegitimacy
• illegitimate
• illegitimate child
• illegitimate enterprise