n.

1. 拘泥形式，拘谨[U][S1]
   I wish we could treat each other without formality.

   我真希望我们彼此之间不要太拘谨。

2. 正式手续[P1]
   It's a formality that we have to go through.

   这是我们必须办理的手续。

3. 礼节；俗套[C]
   All formalities were observed at the ceremony.

   庆典仪式遵循了所有的礼节。

n.

▸something done or happening as a matter of course:

promotion looks a formality.