Definition of "quark" []

• Any of a group of six elementary particles having electric charges of a magnitude one-third or two-thirds that of the electron, regarded as constituents of all hadrons. See Table at subatomic particle. (noun)
• A soft creamy acid-cured cheese of central Europe made from whole milk. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Seeing the word "quark" in James Joyce's "Finnegan's Wake" induced him to make the spelling change."
• "The “beauty” quark is particularly good for probing this question because b-quarks and anti-b-quarks behave “more differently” than other particles and their antimatter counterparts."
• "The heaviest known elementary particle, the top quark is one of the fundamental building blocks of nature and understood to be an ingredient of the nuclear soup just after the Big Bang."