名詞 yawn:

1. an involuntary intake of breath through a wide open mouth; usually triggered by fatigue or boredom
   同義詞：yawning, oscitance, oscitancy

動詞 yawn:

1. utter a yawn, as from lack of oxygen or when one is tired
2. be wide open
   同義詞：gape, yaw

1. His long boring story made me yawn.
   他的冗長的故事聽得我直打呵欠。
2. I gave a loud yawn, but he just kept on talking.
   我大聲打了個呵欠，可他還是不停地講下去。

yawn

v.（動詞）
yawned,yawn.ing,yawns
v.intr.（不及物動詞）
To open the mouth wide with a deep inhalation, usually involuntarily from drowsiness, fatigue, or boredom.
打哈欠：因疲倦、因頓或無聊而不由自主地張大嘴深吸氣
To open wide; gape:
張開；裂開：
例句：
The chasm yawned at our feet.
陷坑在我們的腳下裂開

v.tr.（及物動詞）
To utter wearily, while or as if while yawning:
打著哈欠說：當打著哈欠或似乎打哈欠時，疲倦地說話：
例句：
yawned his disapproval of the silly venture.
對那愚蠢的冒險行動表示意興闌珊

n.（名詞）
The act of yawning.
打哈欠：打哈欠的動作
A fatigued or bored response.
哈欠：疲乏的或厭煩的反應
Informal One that provokes yawns; a bore:
【非正式用語】 讓人打哈欠的事（人）；乏味的事（人）：
例句：
The movie was nothing more than one big yawn.
這部電影只能令人哈欠連天

來源：
Middle English yanen
中古英語 yanen
alteration of yonen, yenen
yonen的變化, yenen
from Old English geonian
源自 古英語 geonian

【引伸】
yawn.er
n.（名詞）