Definitions of substitute:

  • noun:   a person or thing that takes or can take the place of another
  • noun:   an athlete who plays only when another member of the team drops out
  • noun:   someone who takes the place of another (as when things get dangerous or difficult)
  • verb:   put in the place of another; switch seemingly equivalent items
    Example: "Substitute regular milk with fat-free milk"
  • verb:   be a substitute
    Example: "The young teacher had to substitute for the sick colleague"
  • verb:   act as a substitute
  • adjective:   artificial and inferior
    Example: "Substitute coffee"