noun

1. a joining together or being joined together; union; association; combination
2. an occurring together; coincidence the conjunction of events
3. Astrol., Astron. the condition of two or more celestial bodies, esp. a planet with the sun, located along the same celestial longitude when observed from the earth
4. Gram. an uninflected word used to connect words, phrases, clauses, or sentences; connective: conjunctions may be coordinating (Ex.: and, but, or), subordinating (Ex.: if, when, as, because, though), or correlative (Ex.: either . . . or, both . . . and)

Etymology: ME conjunccion < OFr conjunction < L conjunctio < pp. of conjungere: see conjoin