1. the act of making or becoming a single unit

e.g. the union of opposing factions
he looked forward to the unification of his family for the holidays

Synonym: unionunificationunitingjointure

2. the act of pairing a male and female for reproductive purposes

e.g. the casual couplings of adolescents
the mating of some species occurs only in the spring

Synonym: couplingmatingpairingunionsexual union

3. a class of verbs having the same inflectional forms

4. the complete set of inflected forms of a verb

5. the inflection of verbs

6. the state of being joined together

Synonym: junctionconjunctioncolligation