upsilon

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

/ ˈyup səˌlɒn, -lən, ˈʌp-; especially British yupˈsaɪ lən /

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noun

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

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Origin of upsilon

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 )

Words nearby upsilon

upside, upside down, upside-down cake, upsides, upside the head, upsilon, upsilon particle, upsize, upskill, upspin, upspring

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

How to use upsilon in a sentence

The fraternities involved in the alleged drug sales were Alpha Epsilon Pi, Pi Kappa Alpha and Psi Upsilon.
Columbia University Drug Bust|Joshua Robinson, Lloyd Grove|December 8, 2010|DAILY BEAST
The little son of the queen, Prince Upsilon, was peevish over this and was continually calling for more playthings.
Walter Pieterse|Multatuli
It sounds well to be a Kappa Upsilon and we can go around if we like and be as snooty as any of them.
Betty Lee, Sophomore|David Goodger (goodger@python.org)
A bone of the tongue resembling the Greek letter upsilon in shape.
A Treatise on Anatomy, Physiology, and Hygiene (Revised Edition)|Calvin Cutter

This species is the ypsilon of Borkhausen, and the upsilon of other authors.
The Moths of the British Isles, Second Series|Richard South
She issued an order, therefore, that for a certain time Upsilon was to have no playthings.
Walter Pieterse|Multatuli

British Dictionary definitions for upsilon

upsilon

/ (ˈʌpsɪˌlɒn, juːpˈsaɪlən) /

noun

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

Medical definitions for upsilon (1 of 2)

The Greek letter upsilon. Entries beginning with this character are alphabetized under upsilon.

Medical definitions for upsilon (2 of 2)

upsilon

The 20th letter of the Greek alphabet.