tot up vs summate

tot up and summate both are verbs.

Word	Noun	Adjective	Verb	Adverb
tot up	No	No	Yes	No
summate	No	No	Yes	No

As verbs, tot up and summate are synonyms defined as:

Other synonyms of tot up include add, add together, add up, sum, sum up, tally, tot, total, tote up.

tot up (verb)	summate (verb)
determine the sum of	determine the sum of
	form or constitute a cumulative effect