also: ユプシロン · オイプシロン
noun
upsilon
The 20th letter of the Greek alphabet, used in mathematics, physics, and other sciences.
Υはギリシャ文字の一つです。
Upsilon is one of the Greek letters.
物理学では、Υ中間子という粒子がある。
In physics, there is a particle called the upsilon meson.
Alternate katakana spelling, reflecting a different transliteration of the Greek letter.
Rare katakana spelling, based on an older or alternative transliteration.
Epsilon (Ε, ε) is a different Greek letter; upsilon (Υ, υ) is often transliterated as 'u' or 'y'.
From Greek ὖ ψιλόν (û psilón, 'simple u'). The Japanese readings are transliterations of the Greek name.