tot vs add

tot is a noun but add is not a noun.

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

As verbs, tot and add are synonyms defined as:

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

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

tot (verb)	add (verb)
determine the sum of	make an addition (to); join or combine or unite with others; increase the quality, quantity, size or scope of
	make an addition by combining numbers
	determine the sum of
	state or say further
	bestow a quality on
	constitute an addition