breve

[breev, brev] /briv, brɛv/
noun
1.
a mark (˘) over a vowel to show that it is short, or to indicate a specific pronunciation, as ŭ in (kŭt) cut.
2.
Law.
  1. an initial writ.
  2. a writ, as one issued by a court of law.
3.
Music.
  1. the longest modern note, equivalent to two semibreves or whole notes.
  2. Also, brevis. a note in medieval mensural notation equal to one-half or one-third of a longa.
4.
Prosody. a mark (˘) over a syllable to show that it is not stressed.
Origin
1250-1300; Middle English < Medieval Latin, Latin breve, neuter of brevis short; see brief
British Dictionary definitions for breve

breve

/briːv/
noun
1.
an accent, (˘), placed over a vowel to indicate that it is of short duration or is pronounced in a specified way
2.
(music) a note, now rarely used, equivalent in time value to two semibreves
3.
(RC Church) a less common word for brief (sense 7)
Word Origin
C13: from Medieval Latin breve, from Latin brevis short; see brief
Word Origin and History for breve
n.

mid-15c., musical notation indicating two whole notes, from Latin breve (adj.) "short" in space or time (see brief (adj.)). The grammatical curved line placed over a vowel to indicate "shortness" (1540s) is from the same source.