A diminutive word for “mother” in Elvish Hands, Fingers and Numerals from the late 1960s (VT48/6), replacing a longer but rejected diminutive emelig (VT48/6). It is based on either emel “mother” or the primitive root √EM.
Noldorin
nana
noun. mother (hypocoristic), *mommy
A hypocoristic (pet name) for “mother” in The Etymologies of the 1930s derived from the (Noldorin-only?) root ᴹ√NAN (Ety/NAN).
Conceptual Development: The Gnomish Lexicon of the 1910s had the affectionate or childish diminutives {ami, ama >>} G. (m)ami, (m)ama “mummy” (GL/19), as well as G. babi “mummy, mamma” (GL/21).
Neo-Sindarin: I would use S. emig from the late 1960s as the normal diminutive word for “mother” in Neo-Sindarin, but would retain N. nana as a variant.