yo-yo

• n. 溜溜球（一種線軸般的玩具）；優柔寡斷
• adj. 上下起落的；搖擺不定的
• vi. 搖擺不定；上下起落

品牌名，來自菲律賓某語言。

yo-yo (n.)

1915, apparently from a language of the Philippines. Registered as a trademark in Vancouver, Canada, in 1932, the year the first craze for them began (subsequent fads 1950s, 1970s, 1998). The toy itself is much older and was earlier known as bandalore (1802), a word of obscure origin, "but it was from American contact in the Philippines that the first commercial development was established" [Century Dictionary]. Figurative sense of any "up-and-down movement" is first recorded 1932. Meaning "stupid person" is recorded from 1970. The verb in the figurative sense is attested from 1967.