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Webster 1913 Edition
Substract
Sub-stract′
,Verb.
T.
To subtract; to withdraw.
[Obs.]
Barrow.
Webster 1828 Edition
Substract
SUBSTRACT'
,Verb.
T.
Note.--Substract was formerly used in analogy with abstract. But in modern usage, it is written according to the Latin, subtract. See this word and its derivatives.