hemi

¹ American  

[hem-ee] / ˈhɛm i /

noun

Automotive.

1. an internal-combustion engine having hemispherical combustion chambers.

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hemi- ² American  

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

   hemimorphic.

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hemi- British  

prefix

1. half Compare demi- semi-

   hemicycle

   hemisphere

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hemi– Scientific  

1. A prefix meaning “half,” as in hemisphere, half a sphere.

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Usage

What does hemi- mean? Hemi- is a combining form used like a prefix meaning “half.” It is often used in medical terms, especially in pathology and anatomy. Hemi- comes from Greek hēmi-, meaning “half.” The Latin cognate of hēmi- is sēmi-, also meaning “half,” which is the source of English terms such as semicircle and semimonthly. To learn more, check out our entries for both words.

Etymology

Origin of hemi¹

Shortening of hemi-head

Origin of hemi-²

< Greek hēmi- half; cognate with Latin sēmi- semi-

Example Sentences

The guy who won the unlimited fuel class drove a massive machine powered by four blown hemi V-8’s making in excess of 3,000 horsepower.

From Salon • Feb. 6, 2019

A 1956 New Yorker with a hemi engine in it.

From Seattle Times • Oct. 25, 2018

I’ve been lurking on one of the hemi forums again, reading about onging.

From Slate • May 29, 2018

The southern right whale population, which lives in the southern hemi sphere, has been growing by 7–8 percent every year, but figures for North Atlantic right whales are gloomy.

From Scientific American • Aug. 9, 2013

Semi, demi, and hemi, as semicircle, demitone, and hemisphere.

From 1001 Questions and Answers on Orthography and Reading by Hathaway, B. A.