amount vs add up

amount is a noun but add up is not a noun.

Word	Noun	Adjective	Verb	Adverb
amount	Yes	No	Yes	No
add up	No	No	Yes	No

As verbs, amount and add up are synonyms defined as:

Other synonyms of amount include come.

As verbs, amount and add up are synonyms defined as:

Other synonyms of amount include come, number, total.

amount (noun)	add up (noun)
how much there is or how many there are of something that you can quantify
the relative magnitude of something with reference to a criterion
a quantity obtained by the addition of a group of numbers
a quantity of money

amount (verb)	add up (verb)
to measure up to in kind or quality	determine the sum of
add up in number or quantity	be reasonable or logical or comprehensible
be tantamount or equivalent to	to measure up to in kind or quality
	add up in number or quantity