throw in vs add

throw in and add both are verbs.

Word	Noun	Adjective	Verb	Adverb
throw in	No	No	Yes	No
add	No	No	Yes	No

As verbs, add is a hypernym of throw in; that is, add is a word with a broader meaning than throw in:

Other hypernyms of throw in include bestow, bring, contribute, impart, lend.

throw in (verb)	add (verb)
to insert between other elements	make an addition (to); join or combine or unite with others; increase the quality, quantity, size or scope of
give up in the face of defeat of lacking hope; admit defeat	make an addition by combining numbers
add as an extra or as a gratuity	determine the sum of
	state or say further
	bestow a quality on
	constitute an addition