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joint party (e.g. by students from several colleges); combined party; mixer; two or more groups, esp. female and male students, combining for a party
合コンで知り合い交際を始めた。
We met at a mixer and started dating.
初めての合コンで緊張してうまく話せなかった。
At my first mixer I was so nervous I could not speak well.
合コンを企画するのは思ったより大変だと感じた。
I found that organizing a mixer is harder than I thought.