early 15c., from Old French imputer (14c.)
and directly from Latin imputare "to reckon, make account of, charge, ascribe,"
from assimilated form of in- "in, into" (see in- (2)) +
putare "reckon, clear up, trim, prune, settle" from PIE *puto- "cut, struck," suffixed form of root *pau- (2) "to cut, strike, stamp" (see pave).
- I reckon, charge, enter into the account.
- (figuratively) I attribute, credit to; I impute
This answer on Linguistics SE helpfully expounds the Semantic Field of putare.
What are the semantic meaning and role of the prefix 'in-' in imputare?
Please see the titled question.
How did in- augment the semantic field of putare, to enable the semantic shift from 1 to 2?
What semantic notions underlie 1 and 2?
2 overhead contains 'to' in 'attribute, credit to'. So shouldn't ad- have been the prefix? I'm assuming that in- can't signify 'to'.