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quadri-

American  
  1. a combining form meaning “four,” used in the formation of compound words.

    quadrilateral.


quadri- British  

combining form

  1. four

    quadrilateral

    quadrilingual

    quadrisyllabic

"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

Usage

What does quadri- mean? Quadri- is a combining form used like a prefix meaning “four.” It is used in a great variety of technical and scientific terms.Quadri- comes from the Latin quattuor, meaning “four.” The Greek equivalent is tetra-, which also appears as tetr-, as in tetrahedron. Want to know more? Check out our Words That Use entries for tetr- and tetra-.What are variants of quadri-?When combined with words or word elements that begin with a vowel, quadri- becomes quadr-, as in quadric.In other instances, quadri- becomes quadra-, as in quadraphony.Before some labial consonants (such as -p- or -f-), quadri- becomes quadru-, as in quadruplex, which uses the Latin equivalent of the form.Want to learn more? Check out our Words That Use entries for quadr-, quadra-, and quadru-.

Etymology

Origin of quadri-

< Latin; akin to quattuor four