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

1. Express strong disapproval of; deplore
    
2. Belittle
   "The teacher should not deprecate his student's efforts";
   - depreciate, vilipend
    
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

See also: uncomplimentary

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

Encyclopedia: Deprecating