ending vs resultant

ending and resultant both are nouns.

Word	Noun	Adjective	Verb	Adverb
ending	Yes	No	No	No
resultant	Yes	Yes	No	No

As nouns, resultant is a hyponym of ending; that is, resultant is a word with a more specific, narrower meaning than ending:

ending (noun)	resultant (noun)
the act of ending something	a vector that is the sum of two or more other vectors
the end of a word (a suffix or inflectional ending or final morpheme)	something that results
the last section of a communication	the final point in a process
event whose occurrence ends something
the point in time at which something ends

ending (adjective)	resultant (adjective)
	occurring with or following as a consequence