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Webster 1913 Edition
Semibreve
Sem′i-breveˊ
,Noun.
[Pref.
semi-
+ breve
: cf. F. semi-breve
, It. semibreve
.] [Formerly written
semibref
.] (Mus.)
A note of half the time or duration of the breve; – now usually called a whole note. It is the longest note in general use.