nail down vs terminate

nail down and terminate both are verbs.

Word	Noun	Adjective	Verb	Adverb
nail down	No	No	Yes	No
terminate	No	No	Yes	No

As verbs, terminate is a hypernym of nail down; that is, terminate is a word with a broader meaning than nail down:

Other hypernyms of nail down include end.

nail down (verb)	terminate (verb)
make final; put the last touches on; put into final form	bring to an end or halt
define clearly	terminate the employment of; discharge from an office or position
succeed in obtaining a position	have an end, in a temporal, spatial, or quantitative sense; either spatial or metaphorical
	be the end of; be the last or concluding part of