substitute
noun
a person or thing that takes or can take the place of another
Synonymsreplacementan athlete who plays only when a starter on the team is replaced
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”
verb
put in the place of another; switch seemingly equivalent items
“the con artist replaced the original with a fake Rembrandt”
“substitute regular milk for 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”
adjective
Source: WordNet 3.1, Princeton University
