1. Tending to diminish or disparage
   "managed a deprecating smile at the compliment";
   - belittling, deprecative, deprecatory, depreciative, depreciatory, slighting, depreciating

1. Express strong disapproval of; deplore
   "The committee deprecated the use of such aggressive tactics"
    
2. Belittle
   "The teacher should not deprecate his student's efforts";
   - depreciate, vilipend [archaic]
    
3. (computing) declare something obsolescent; recommend against a function, technique, command, etc, that still works but has been replaced and may not work in future
   "The programming language deprecated several old functions in its latest version"

See also: uncomplimentary

Type of: belittle, disapprove, disparage, pick at, reject

Encyclopedia: Deprecating