summate vs tot

summate is not a noun while tot is a noun.

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

As verbs, summate and tot are synonyms defined as:

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

summate (noun)	tot (noun)
	a young child who is just beginning to walk
	a small amount (especially of a drink)

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