μῦ
μῦ, τό, name of the letter μ, IG 2.4321.24 (iv B. C.), Epigr. ap. , 10.454f ap. Bibl. p.530 , etc.
2). μῦ or μὺ μῦ, to represent a muttering sound made with the lips, μῦ λαλεῖν to mutter, (dub. l.); to imitate the sound of 80 sobbing, μὺ μῦ, μὺ μῦ Eq. 10 .