prac·tic·er noun orprac·tis·er\-sə(r)\ (-s) Etymology: Middle English practisour, from practisen + -our -or : one that practices: as a.: one that exercises a profession : practitioner b.: a habitual performer of a particular act < man as a maker and practicer of culture — T.D.McCown > especially: an adherent of a faith or code of behavior < a practicer of yogi > c.: schemer, plotter