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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His boss, whom he admires, is waiting to meet with him about the big project.

His boss, who he admires, is waiting to meet with him about the big project.

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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. 2023

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