1. Impossible to achieve
   "an unattainable goal"
   - unachievable, undoable, unrealizable, unrealisable [Brit]

See also: impossible, unattainableness

• nonsexual
• nonsignificant
• nonsingular matrix
• nonskid
• nonslip
• nonslippery
• nonsmoker
• nonsmoking
• nonsmoking car
• nonsocial
• nonsocial infection
• nonsolid color
• nonsolid colour
• nonsovereign
• nonspatial
• nonspeaking
• nonspecific
• nonspecific urethritis
• nonspecifically
• nonspherical
• nonstandard
• nonstarter
• nonsteroid
• nonsteroidal
• nonsteroidal anti-inflammatory