LATIN DICTIONARYLexicon Latīnum
letter

◌̄̆

Meaning

  1. diacriticuncertain vowel length
  2. diacriticvariable vowel length
    gen. illī̆us (usu. illĭus in epic and lyric poets; Cic. de Or. 3, 47, 183; illīus in the time of Quint1879, Charlton T. Lewis, Charles Short, A Latin Dictionary (overall work in English), Oxford: Clarendon Press, ille:
  3. diacriticvariable syllable weight (due to alternative syllabification of consonant clusters)
    cĕlĕber, ē̆bris, ē̆bre, adj.1879, Charlton T. Lewis, Charles Short, A Latin Dictionary (overall work in English), Oxford: Clarendon Press, celeber:

Quick answers

What does ◌̄̆ mean in Latin?
◌̄̆, a letter, means “uncertain vowel length; variable vowel length; variable syllable weight (due to alternative syllabification of consonant clusters)”.