plural semis
Definition of semi
(Entry 1 of 4)
: semifinal
—often used in plural
semi
noun (2)
plural semis
Definition of semi (Entry 2 of 4)
semi
noun (3)
plural semis
Definition of semi (Entry 3 of 4)
chiefly British
: a semidetached house
semi-
prefix
\ ˌse-mē, -ˌmī, -mi \
Definition of semi- (Entry 4 of 4)
1a
: 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-
3a
: partial : incomplete
semiconsciousness semidarkness
b
: having some of the characteristics of
semiporcelain
c
: quasi-
semigovernmental semimonastic
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Merriam-Webster unabridged
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Time Traveler for semi
The first known use of semi was in 1912
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