To foregather is to meet in a group — friends turning up in the same café, old classmates finding one another at a party. It often has a warm, social feel: people are not so much called to a meeting as they come together in one place. It is an old-fashioned, bookish word; most people today just say gather or meet. You may also see it spelled forgather. You will meet it in stories and older writing far more than in emails or everyday speech. If you use it in casual talk, some listeners will understand, and some will only hear a fancy way of saying meet.

聚集、相聚（偏文雅、舊式）