A noun glossed “dance” in the Gnomish Lexicon of the 1910s (GL/70), clearly based on the early root ᴱ√TṆTṆ (QL/93), probably with [[g|short syllabic [ṇ] becoming [in]]]. It had a past form {tinti >>} tanti showing the development of [[g|long syllabic [ṇ̄] to [an]]].
Gnomish
laltha-
verb. to dance
tinta-
verb. to dance
A word appearing as G. laltha- “to dance” in the Gnomish Lexicon of the 1910s, a verb form of G. lalt “a dance” (GL/52).
Neo-Sindarin: For purposes of Neo-Sindarin, I would adapt this word as ᴺS. liltha- for better compatibility with the later root ᴹ√LILT “dance”.