Source : Webster's Revised Unabridged Dictionary (1913)

Modifier \Mod"i*fi`er\, n.
   One who, or that which, modifies. --Hume.

Source : WordNet®

modifier
     n 1: a content word that qualifies the meaning of a noun or verb
          [syn: {qualifier}]
     2: a moderator who makes less extreme or uncompromising
     3: a person who changes something; "an inveterate changer of
        the menu" [syn: {changer}]
     4: a gene that modifies the effect produced by another gene
        [syn: {modifier gene}]

Source : Free On-Line Dictionary of Computing

modifier
     
         An operation that alters the state of an
        {object}.  Modifiers often have names that begin with "set"
        and corresponding {selector} functions whose names begin with
        "get".
     
        (1998-01-12)