n.

1. 呵欠[C]
   He stretched himself with a yawn.

   他打了个呵欠伸了伸懒腰。

2. 裂口，豁口；凹口[C]
3. 【口】乏味的人（或事）[S]
   The play was a big yawn from start to finish.

   那出戏从头至尾极其乏味。

vi.

1. 打呵欠
   Mr. Walsh yawned over the evening papers.

   华尔希先生一边看晚报一边打呵欠。

2. 裂开，豁开
   A big gap yawned between the rocks.

   岩石间豁开一个大裂口。

vt.

1. 打着呵欠说
   The old man yawned a reply.

   那老人打着呵欠作答。

v.

1. involuntarily open one's mouth wide and inhale deeply due to tiredness or boredom.
2. [usu. as adj. yawning] be wide open:
   a yawning chasm.

n.

1. an act of yawning.
2. informal a boring or tedious thing or event.