/ sʌbstətuːt /
replacement · reserve
ETYM Latin substitutus, p. p. of substituere to put under, put in the place of; sub under + statuere to put, place: cf. French substitut. Related to Statute.
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.