a person or thing that takes or can take the place of another
an athlete who plays only when a starter on the team is replaced
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"
be a substitute; "The young teacher had to substitute for the sick colleague"; "The skim milk substitutes for cream--we are on a strict diet"
act as a substitute; "She stood in for the soprano who suffered from a cold"
someone who is appointed or elected to an office and who holds a position of trust; "he is an officer of the court"; "the club elected its officers for the coming year"
being the agent or cause; "determined who was the responsible party"; "termites were responsible for the damage"
worthy of or requiring responsibility or trust; or held accountable; "a responsible adult"; "responsible journalism"; "a responsible position"; "the captain is responsible for the ship's safety"; "the cabinet is responsible to the parliament"