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

Examples of semi in a Sentence

Recent Examples on the Web
Noun
All lanes were opened just before 8 a.m. The crash was reported at 1:40 a.m. when an SUV and semi collided in the southbound lanes near the Western Row Road exit, according to a dispatcher at the Ohio State Highway Patrol’s Lebanon post. Jennifer Edwards Baker, The Enquirer, 16 May 2024 Pennsylvania State Police troopers said Richmond, who was not in a vehicle, was struck by a semi just after 6 p.m. Mike Stunson, Miami Herald, 14 May 2024 The officer and trooper located the semi about 30 minutes later and conducted a traffic stop. Stephen Sorace, Fox News, 6 May 2024 Authorities are continuing to investigate who was riding on top of the semi’s trailer. Stephen Sorace, Fox News, 6 May 2024 His semi was discovered the afternoon of Nov. 21 after sitting there since early in the morning, according to the sheriff. Mike Stunson, Kansas City Star, 25 Apr. 2024 The Iowa Department of Public Safety said someone in his field discovered a body Wednesday, near where 53-year-old David Schultz's semi was found parked in the middle of the road on Nov. 21. CBS News, 25 Apr. 2024 The van was on its side, and the front of the semi was mangled as the big rig and its load lay in a ditch by the highway, partially on its side. Marlene Lenthang, NBC News, 9 Mar. 2024 The driver of the semi was not under the influence of drugs or alcohol, the CHP said. Rosalio Ahumada, Sacramento Bee, 7 Mar. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'semi.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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 3 Jun. 2024.

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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