throw in vs interject

throw in and interject both are verbs.

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

As verbs, throw in and interject are synonyms defined as:

Other synonyms of throw in include come in, inject, interpose, put in.

throw in (verb)	interject (verb)
to insert between other elements	to insert between other elements
give up in the face of defeat of lacking hope; admit defeat
add as an extra or as a gratuity