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
According to details released by the Clark County Sheriff's Office, a preliminary report indicated the semi and the passenger van collided at the intersection of the two highways. Drew Dawson, Journal Sentinel, 9 Mar. 2024 The semi struck Light's Chevrolet Cruze from behind and caused his car to go off the right side of the road. Erin Couch, The Enquirer, 21 Feb. 2024 The semi, which was not hauling a trailer at the time of the incident, was unusual in that it wasn’t powered by diesel. Hannah Fry, Los Angeles Times, 16 Feb. 2024 All occupants of the semi and train were uninjured. Mike Stunson, Kansas City Star, 8 Feb. 2024 Then, a second semi appears in the video and gets stuck on the tracks when the barrier dropped between the semi’s cab and trailer. Mike Stunson, Kansas City Star, 8 Feb. 2024 Upon arriving on the scene, Majeski entered the cab of the burning semi and pulled the unconscious driver to safety, saving his life. Anna Pearson, Twin Cities, 8 Feb. 2024 According to police, investigators determined the tractor trailer was attempting to turn left from Jarvis onto the westbound lane of Bailey Boswell when a motorcycle traveling eastbound hit the rear of the semi. Harriet Ramos, Fort Worth Star-Telegram, 31 Jan. 2024 The 37-year-old driver of the semi was not injured. Kristina Davis, San Diego Union-Tribune, 27 Oct. 2023

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 29 Mar. 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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