To deduct is defined as to subtract or take away from a total.(verb)
If you have four cookies and someone takes two and you now only have two, this is an example of when someone deducts two cookies.
See deduct in Webster's New World College Dictionary
Origin: ME deducten < L deductus, pp. of deducere: see deduce
See deduct in American Heritage Dictionary 4
verb de·duct·ed, de·duct·ing, de·ducts verb, transitive
Origin: Middle English deducten
Origin: , from Latin dēdūcere, dēduct-, to lead away or down; see deduce.
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