I. noun
1.
a person who takes the place of or acts instead of another
found a substitute for the sick teacher
Synonyms: alternate, backup, fill-in, locum tenens, pinch hitter, replacement, stand-in, sub, succedaneum, surrogate
Related Word: relay, relief; deputy, procurator, proxy; supply; double, understudy
2.
Synonyms: resource 3, dernier ressort, expediency, expedient, makeshift, recourse, refuge, resort, stopgap, surrogate
II. verb
Synonyms: exchange 2, change, swap, switch, trade
III. adjective
1.
serving or fitted for use as a substitute
a substitute driver was needed for the long trip
Synonyms: alternate, alternative, backup, surrogate
Related Word: additional, another; other, second; reserve; supplemental, supplementary, suppletory
2.
Synonyms: artificial 2, dummy, ersatz, false, imitation, mock, sham, simulated, spurious