junction vs tangency

junction and tangency both are nouns.

Word	Noun	Adjective	Verb	Adverb
junction	Yes	No	No	No
tangency	Yes	No	No	No

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

junction: something that joins or connects
tangency: (electronics) a junction where things (as two electrical conductors) touch or are in physical contact

Other hyponyms of junction include contact, joint, barrier strip, junction barrier, splice, splicing, thermojunction.

junction (noun)	tangency (noun)
an act of joining or adjoining things	(electronics) a junction where things (as two electrical conductors) touch or are in physical contact
the place where two or more things come together	the state of being tangent; having contact at a single point or along a line without crossing
something that joins or connects
the shape or manner in which things come together and a connection is made
the state of being joined together