Lewis & Short

1. mammŭla, ae, f. dim. [mamma], a little breast or teat.

  1. I. Lit., Varr. R. R. 2, 3, 2; Cels. 7, 26, 1.
  2. II. Transf., in the language of children, little mamma, mammy, Inscr. Orell. 4849; 4671; cf. mamma, II. B.