cum
Cum (preposition) means Combined with; serving as both one thing and another. Example: “They converted the garage into a gym-cum-workshop at the back of the house.”
How to use cum
Learner’s notesIn plain EnglishAs a linking word it means "combined with" (a kitchen-cum-dining room). As slang it's a vulgar term for semen.
The "combined with" use is formal/literary; the slang sense is vulgar and inappropriate for most writing.
Etymology
The "combined with" sense is a learned borrowing of the Latin word cum, meaning "with."