breakthrough vs insight

breakthrough and insight both are nouns.

Word	Noun	Adjective	Verb	Adverb
breakthrough	Yes	No	No	No
insight	Yes	No	No	No

As nouns, insight is a hypernym of breakthrough; that is, insight is a word with a broader meaning than breakthrough:

Other hypernyms of breakthrough include brainstorm, brainwave.

breakthrough (noun)	insight (noun)
a penetration of a barrier such as an enemy's defense	grasping the inner nature of things intuitively
making an important discovery	the clear (and often sudden) understanding of a complex situation
a productive insight	clear or deep perception of a situation
	a feeling of understanding