WordWeb Online

1. Something immaterial that stands in the way and must be circumvented or surmounted
   "lack of imagination is an obstacle to one's advancement"; "the poverty of a district is an obstacle to good education";
   - obstruction
    
2. An obstruction that stands in the way (and must be removed, surmounted or circumvented)

Derived forms: obstacles

Type of: balk, baulk [Brit], check, deterrent, handicap, hinderance, hindrance, impediment, impedimenta, obstructer, obstruction, obstructor

Encyclopedia: Obstacle