"Three way" vs. "Threesome" [closed]

My apology if I'm disrespecting the forum with such question, but after all we are here to learn. Are three way and threesome different from each other? Have I written "Three way" correctly?


A threesome is a group of three people.

A three-way is a sex-act performed by a group of three people, or as a modifier, it can refer to a situation involving three entities, as in

There was a three-way tie for first place. What an amazing photo-finish!