名詞 yo-yo:

1. a toy consisting of a spool that is reeled up and down on a string by motions of the hand

1. The price of petrol is going up and down like a Yo-Yo.
   汽油的價格像悠悠一樣忽上忽下。

yo-yo

n.（名詞）
【復數】 yo-.yos
A toy consisting of a flattened spool wound with string that is spun down from and reeled up to the hand by motions of the wrist.
游游拉線盤，溜溜球：由纏有細繩的扁線盤構成的玩具，通過手腕運動在手上翻轉，然后收到手里
Informal One that undergoes frequent abrupt shifts or reversals, as of opinion or emotion; a vacillator.
【非正式用語】 優(yōu)柔寡斷的人：經常突然變換或徹底改變的人，如看法或感情；猶豫不決的人
Slang A person regarded as stupid or objectionable.
【俚語】 笨蛋，蠢人：被認作是愚蠢或令人討厭的人
v.intr.（不及物動詞）
yo-.yoed,yo-.yo.ing,yo-.yos 【非正式用語】
To undergo frequent abrupt shifts or reversals, as of opinion or emotion; vacillate.
猶豫不決：經常突然變換或徹底改變看法或感情；猶豫

來源：
[Originally a trademark]
[原先是一商標]