servicing vs coupling

servicing and coupling both are nouns.

Word	Noun	Adjective	Verb	Adverb
servicing	Yes	No	No	No
coupling	Yes	No	No	No

As nouns, coupling is a hypernym of servicing; that is, coupling is a word with a broader meaning than servicing:

Other hypernyms of servicing include conjugation, mating, pairing, sexual union, union.

servicing (noun)	coupling (noun)
the act of mating by male animals	the act of pairing a male and female for reproductive purposes
	a mechanical device that serves to connect the ends of adjacent objects
	a connection (like a clamp or vise) between two things so they move together