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
The semi was engulfed in flames when police and fire crews responded around 4:30 a.m. The fire was quickly put out and contained to the cab of the semi. Jennifer Edwards Baker, The Enquirer, 11 June 2024 Authorities say Heflin jumped out and climbed onto the hood of the semi as police swarmed her and took her into custody. Nathan Solis, Los Angeles Times, 23 May 2024 The truck is based on Volvo’s new VNL, which is a Class 8 semi truck built for long-haul transportation. Andrew J. Hawkins, The Verge, 21 May 2024 The interstate shut down shortly after 9:30 a.m. when the semi crashed and overturned, said Cpl. Robert A. Cronkleton, Kansas City Star, 30 May 2024 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

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 23 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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