汉：来源于拉丁语，意为“beyond,exceeding”，可变形为ulter。
英：prefix meaning "beyond" (ultraviolet) or "extremely" (ultramodern), from L. ultra- from ultra (adv. and prep.) "beyond, on the further side," from PIE *al- "beyond." In common use from early 19c., it appears to have arisen from French political designations. As its own word, a noun meaning "extremist" of various stripes, it is first recorded 1817, from Fr. ultra, shortening of ultra-royaliste "extreme royalist."
1.表示“极端”
ultra-democracy 极端民主 ultrapure 极纯的
ultra-reactionary 极端反动的 ultra-left 极左的 2.表示“超，以外”
ultrasonic
a.relating to sound waves beyond the range of normal human audibility 超声的，超音的 前缀ultra=beyond,词根son=sound,-ic在此为形容词后缀。
long-term exposure to ultrasonic sound can damage your hearing.
长期处在超声环境中，会损伤你的听觉
ultraviolet
a.of the invisible part of the spectrum beyond the violet 紫外（线）的 violet=violet ray
Honey bees see only ultraviolet light,so they see flowers quite differently than we do.
蜜蜂能看到紫外线，所以它们看到的花朵与我们看到的截然不同。