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hepta-

American  
especially before a vowel, hept-.
  1. a combining form meaning “seven,” used in the formation of compound words.

    heptahedron.


hepta- British  

combining form

  1. seven

    heptameter

"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 hepta- mean? Hepta- is a combining form used like a prefix meaning “seven.” It is used in a number of scientific and other technical terms.In chemistry, hepta- is specifically used to indicate seven atoms or seven groups of atoms in compounds, e.g., heptachlor.Hepta- comes from the Greek heptá, meaning “seven.” The English word seven, as different as it may look, is actually related to the Greek heptá.What are variants of hepta-?When combined with words or word elements that begin with a vowel, hepta- becomes hept-, as in heptane.

Etymology

Origin of hepta-

< Greek, combining form of heptá seven; cognate with Latin septem; akin to Old English seofon seven