hindsight vs apprehension

hindsight and apprehension both are nouns.

Word	Noun	Adjective	Verb	Adverb
hindsight	Yes	No	No	No
apprehension	Yes	No	No	No

As nouns, apprehension is a hypernym of hindsight; that is, apprehension is a word with a broader meaning than hindsight:

Other hypernyms of hindsight include discernment, savvy, understanding.

hindsight (noun)	apprehension (noun)
understanding the nature of an event after it has happened	the act of apprehending (especially apprehending a criminal)
	the cognitive condition of someone who understands
	painful expectation
	fearful expectation or anticipation