pairing vs grouping

pairing and grouping both are nouns.

Word	Noun	Adjective	Verb	Adverb
pairing	Yes	No	No	No
grouping	Yes	No	No	No

As nouns, grouping is a hypernym of pairing; that is, grouping is a word with a broader meaning than pairing:

pairing (noun)	grouping (noun)
the act of pairing a male and female for reproductive purposes	any number of entities (members) considered as a unit
the act of grouping things or people in pairs	the activity of putting things together in groups
	a system for classifying things into groups