[ yoop-suh-lon, -luh n, uhp-; especially British yoop-sahy-luh n ]
/ ˈyup səˌlɒn, -lən, ˈʌp-; especially British yupˈsaɪ lən /
the 20th letter of the Greek alphabet (Υ, υ).
the vowel sound represented by this letter.
Also called upsilon particle. Physics. any of a family of heavy, short-lived, neutral mesons that are composed of a bottom quark and its antiquark. Symbol: Υ, υ
These Words Were Too Awkward To Stay In Regular UseRead more in this article about some frequently asked questions and fun facts related to our definitions.
The Wittiest Vegan Names For Animal-alternativesWe know the word vegan came about in the 1800s, but what about the other terms that relate to veganism? Let's take a look at what vegans call their versions of animal products and where they came up with the names. Note: These may not be the most popular names for these vegan items, but they're definitely the most entertaining.
- upside down,
- upside the head,
- upside-down cake,
- upsilon particle,
Origin of upsilon
1615–25; < Late Greek ŷ psīlón literally, simple u (to distinguish it from the digraph oi, pronounced the same in LGk)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
/ (ˈʌpsɪˌlɒn, juːpˈsaɪlən) /
the 20th letter in the Greek alphabet (Υ, υ), a vowel, transliterated as y or u
Word Origin for upsilon
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
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
"20th letter of the Greek alphabet," 1640s, from Greek u psilon, literally "a mere (or bare) 'u;' " so called in contradistinction to the diphthongs -oi-, -ei-, which are pronounced exactly like upsilon.
Online Etymology Dictionary, © 2010 Douglas Harper
The 20th letter of the Greek alphabet.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
[ ŭp′sə-lŏn′, yōōp′- ]
An electrically neutral meson having a mass 18,513 times that of the electron and a mean lifetime of approximately 8.0 X 10-20 seconds. See Table at subatomic particle.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.