1

semi

noun \ ˈse-mē also -ˌmī \

Definition of semi

plural semis
chiefly British
: a semidetached house

Origin and Etymology of semi

short for semidetached

2

semi

noun \ ˈse-ˌmī also -mē \

Definition of semi

plural semis

First Known Use of semi

1942

Other Automotive Terms


3

semi

noun \ ˈse-ˌmī also -mē \

Definition of semi

plural semis
: semifinal often used in plural

First Known Use of semi

1942


semi-

prefix \ ˌse-mē , -ˌmī , -mi \

Definition of semi-

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

Origin and Etymology of semi-

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

SEMI Defined for English Language Learners

semi-

prefix

Definition of semi- for English Language Learners

  • : half

  • : happening twice during a particular period of time

  • : partly : not completely


SEMI Defined for Kids

semi-

prefix

Definition of semi- for Students

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


Seen and Heard

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