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1. (usually followed by 'to') naturally disposed toward
   "he is apt to ignore matters he considers unimportant";
   - disposed, given, minded, tending
    
2. At risk of or subject to experiencing something usually unpleasant
   "he is apt to lose";
   - liable
    
3. Mentally quick and resourceful
   "an apt pupil";
   - clever
    
4. Being of striking appropriateness and pertinence
   "an apt reply";
   - apposite, pertinent

Derived forms: aptest, apter

See also: apropos, inclined, intelligent, likely

Encyclopedia: Apt, Vaucluse