measure word · classifier for a lump, wad, or soft mass like wool or smoke

山间升起了一团白雾。

noun · a specific group of atoms within a molecule that is responsible for the characteristic chemical reactions of those molecules

这个分子的侧链上含有一个具有特定活性的官能团。

noun, measure word · a round mass or lump

猫在地上玩一个毛线团。

noun, punctuation · an organized group, society, or military regiment

他报名参加了一个去北京的旅游团。

verb, measure word · to roll something into a ball or to gather together

他把信纸团起来，扔进了废纸篓里。