/ səbˈstænʃl; NAmE / adjective
1.
large in amount, value or importance
SYN considerable :
substantial sums of money
a substantial change
Substantial numbers of people support the reforms.
He ate a substantial breakfast.
2.
[ usually before noun ] ( formal ) large and solid; strongly built :
a substantial house
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WORD ORIGIN
Middle English : from Old French substantiel or Christian Latin substantialis , from substantia being, essence, from substant- standing firm, from the verb substare .