semi

1 of 4

noun (1)

plural semis
: semifinal
often used in plural

semi

2 of 4

noun (2)

plural semis

semi

3 of 4

noun (3)

plural semis
chiefly British
: a semidetached house

semi-

4 of 4

prefix

ˌse-mē,
-ˌmī,
-mi
1
a
: 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-
3
a
: partial : incomplete
semiconsciousness
semidarkness
b
: having some of the characteristics of
semiporcelain
c
: quasi-
semigovernmental
semimonastic

Example Sentences

Recent Examples on the Web
Noun
Princeton, 25-2 overall, advances to Saturday’s regional final, 7 p.m. at Lakota West, against the winner of Wednesday night’s semi between Kings and Lakota East. James Weber, The Enquirer, 2 Mar. 2023 The 22 semi-finalists of the 2023 LVMH Prize presented their collections at 22 Avenue Montaigne tonight at a cocktail that was packed to the rafters within minutes of opening. Luke Leitch, Vogue, 2 Mar. 2023 The sedan rotated and the right side of the vehicle collided into the rear of a 34-year-old man’s 2020 semi-truck with a trailer that was stopped for traffic on the outside lane on Florida’s Turnpike. Elainie Barraza, Orlando Sentinel, 25 Feb. 2023 Because of that, the company built up a large delivery fleet which reportedly includes 70 airplanes, 40,000 semi-trailers and 30,000 vans. Ana Faguy, Forbes, 22 Feb. 2023 His vehicle hit the semi and also struck another vehicle, and the man was pronounced dead at the scene, state police said, citing the results of a preliminary investigation. Mike Nolan, Chicago Tribune, 22 Feb. 2023 Officials also cautioned drivers of commercial vehicles, like semi-trucks, which can be knocked over by strong gusts. Orlando Mayorquin, USA TODAY, 13 Feb. 2023 The Biden Administration has slapped stiff controls on the export of equipment to manufacture advanced semi-conductors and just this week persuaded Japan and the Netherlands to sign on. David A. Andelman, CNN, 4 Feb. 2023 At one scene Tuesday afternoon, semi-trucks struggled to make it up a hill on westbound Interstate 20 at Cedar Ridge near Loop 408. Dallas News, 31 Jan. 2023 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'semi.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

Etymology

Noun (3)

short for semidetached

Prefix

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

First Known Use

Noun (1)

1942, in the meaning defined above

Noun (2)

1942, in the meaning defined above

Noun (3)

1912, in the meaning defined above

Time Traveler
The first known use of semi was in 1912

Dictionary Entries Near semi

Cite this Entry

“Semi.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/semi. Accessed 28 Mar. 2023.

Kids Definition

semi-

prefix
ˌsem-i,
ˈsem-,
-ˌī
1
: half in amount or value
semitone
2
: occurring halfway through a certain time period
semiannual
3
: to some extent : partly : incompletely
semitropical
4
: partial : incomplete
semidarkness
Etymology

Prefix

Latin semi- "half"

More from Merriam-Webster on semi

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