\ ˈse-mē How to pronounce semi (audio) also -ˌmī How to pronounce semi (audio) \
plural semis

Definition of semi

 (Entry 1 of 4)

chiefly British
: a semidetached house
\ ˈse-ˌmī How to pronounce semi (audio) also -mē How to pronounce semi (audio) \
plural semis

Definition of semi (Entry 2 of 4)

\ ˈse-ˌmī How to pronounce semi (audio) also -mē How to pronounce semi (audio) \
plural semis

Definition of semi (Entry 3 of 4)

: semifinal often used in plural

semi-

prefix
\ ˌse-mē, -ˌmī, -mi \

Definition of semi- (Entry 4 of 4)

1a : precisely half of:
(1) : forming a bisection of semidiameter
(2) : being a usually vertically bisected form of (a specified architectural feature) semidome
b : half in quantity or value : half of or occurring halfway through a specified period of time semiannual semimonthly — compare bi-
2 : to some extent : partly : incompletely semicivilized semi-independent semidry — compare demi-, hemi-
3a : partial : incomplete semiconsciousness semidarkness
b : having some of the characteristics of semiporcelain
c : quasi- semigovernmental semimonastic

First Known Use of semi

Noun (1)

1912, in the meaning defined above

Noun (2)

1942, in the meaning defined above

Noun (3)

1942, in the meaning defined above

History and Etymology for semi

Noun (1)

short for semidetached

Prefix

Middle English, from Latin; akin to Old High German sāmi- half, Greek hēmi-

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Last Updated

27 Apr 2020

Cite this Entry

“Semi.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/semi. Accessed 29 May. 2020.

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More Definitions for semi

semi-

prefix

English Language Learners Definition of semi-

: half
: happening twice during a particular period of time
: partly : not completely

semi-

prefix

Kids Definition of semi-

1 : half semicircle
2 : partly : not completely
3 : partial

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More from Merriam-Webster on semi

Thesaurus: All synonyms and antonyms for semi

Rhyming Dictionary: Words that rhyme with semi

Nglish: Translation of semi for Spanish Speakers

Britannica English: Translation of semi for Arabic Speakers

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