upsilon

[ yoop-suh-lon, -luhn, uhp-; especially British yoop-sahy-luhn ]

noun

1. the 20th letter of the Greek alphabet (Υ, υ).
2. the vowel sound represented by this letter.
3. Also called upsilon particle. Physics. any of a family of heavy, short-lived, neutral mesons that are composed of a bottom quark and its antiquark. : Υ, υ

upsilon

/ ˈʌpsɪˌlɒn; juːpˈsaɪlən /

noun

1. the 20th letter in the Greek alphabet (Υ, υ), a vowel, transliterated as y or u

Word History and Origins

Origin of upsilon¹

First recorded in 1615–25; from Late Greek ŷ psīlón, literally, “simple u ” (to distinguish it from the digraph oi, pronounced the same in Late Greek )

Word History and Origins

Origin of upsilon¹

C17: from Medieval Greek u psilon simple u, name adopted for graphic u to avoid confusion with graphic oi, since pronunciation was the same for both in Late Greek

Example Sentences

And Last: The Empress comes down with a breakthrough case of the upsilon variant and loses her senses of taste and humor.

From Washington Post

They named the signal upsilon, after the shape of the decay-particle trajectories, which resembled the Greek letter.

From Nature

On the other hand, alpha and pi are nearer the model of Codex B. Iota and upsilon, which in Cod.

From Project Gutenberg

Instead, the limited evidence now available suggests that T. tau and T. upsilon are names based on a highly variable character of color pattern of the head, and that only one species is involved.

From Project Gutenberg

Changed what appeared to be upsilon with inverted breve to upsilon with perispomeni in the Greek on page 2.

From Project Gutenberg