■ noun
1》 a person or thing acting or serving in place of another.
2》 a sports player nominated as eligible to replace another after a match has begun.
3》 Scots Law a deputy.
■ verb
1》 (usu. ~ something for ) use, add, or serve in place of.
↘(usu. ~ something with ) replace with another.
↘ Chemistry replace (an atom or group in a molecule) with another.
2》 replace (a sports player) with a ~ during a match.
Derivatives
substitutability noun
substitutable adjective
substitutive adjective
Origin
ME (denoting a deputy or delegate): from L. substitut- , substituere 'put in place of'.
Usage
Traditionally, the verb ~ is followed by for and means ‘put (someone or something) in place of another’, as in she ~d the fake vase for the real one . More recently it has also been used with with or by to mean ‘replace (something) with something else’, as in she ~d the real vase with the fake one . Though still disapproved of by traditionalists, this use is now generally regarded as part of standard English.