sum total vs sum

sum total and sum both are nouns.

Word	Noun	Adjective	Verb	Adverb
sum total	Yes	No	No	No
sum	Yes	No	Yes	No

As nouns, sum total and sum are synonyms defined as:

Other synonyms of sum total include summation.

sum total (noun)	sum (noun)
the final aggregate	the whole amount
	the choicest or most essential or most vital part of some idea or experience
	a quantity obtained by the addition of a group of numbers
	the final aggregate
	a set containing all and only the members of two or more given sets
	a quantity of money

sum total (verb)	sum (verb)
	determine the sum of
	be a summary of