windup vs completion

windup and completion both are nouns.

Word	Noun	Adjective	Verb	Adverb
windup	Yes	Yes	No	No
completion	Yes	No	No	No

As nouns, windup and completion are synonyms defined as:

Other synonyms of windup include closing, culmination, mop up.

windup (noun)	completion (noun)
a concluding action	a concluding action
	(American football) a successful forward pass in football

windup (adjective)	completion (adjective)
operated by a mechanism