Late 16th century; earliest use found in John Payne (fl. 1597). From classical Latin substant-, substāns, present participle of substāre. With use as noun compare post-classical Latin substantia (neuter plural) existence.
Definition of substant in US English:
substant
nounˈsʌbstənt
rare
Something that subsists.
adjectiveˈsʌbstənt
rare
Substantial; subsistent.
Origin
Late 16th century; earliest use found in John Payne (fl. 1597). From classical Latin substant-, substāns, present participle of substāre. With use as noun compare post-classical Latin substantia (neuter plural) existence.