substitute

substitute (http://definr.com/substitute)

     adj 1: being a replacement or substitute for a regular member of a
            team [syn: second-string, substitute(a)]
     2: capable of substituting in any of several positions on a
        team; "a utility infielder" [syn: utility(a), substitute(a)]
     3: artificial and inferior; "ersatz coffee"; "coffee
        substitute" [syn: ersatz, imitation, substitute(p)]
     n 1: a person or thing that takes or can take the place of
          another [syn: replacement]
     2: an athlete who plays only when another member of the team
        drops out [syn: reserve]
     3: someone who takes the place of another (as when things get
        dangerous or difficult); "the star had a stand-in for
        dangerous scenes"; "we need extra employees for summer
        fill-ins" [syn: stand-in, relief, reliever, backup,
         backup man, fill-in]
     v 1: put in the place of another; switch seemingly equivalent
          items; "the con artist replaced the original with a fake
          Rembrandt"; "substitute regular milk with fat-free milk"
          [syn: replace]
     2: be a substitute [syn: sub, stand in, fill in]
     3: act as a substitute for [syn: deputize, deputise, {stand
        in}, step in]