A noun appearing as (n)gôl “slaughter” in the Gnomish Lexicon of the 1910s (GL/41). Its etymology is unclear.
Gnomish
nanc
noun. bite
(n)gôl
noun. slaughter
mal-
verb. to chew
A verb appearing as G. mal- “to chew” in the Gnomish Lexicon of the 1910s (GL/56), perhaps based on the early root ᴱ√MALA “crush” (QL/58).
Neo-Sindarin: The root became ᴹ√MBAL in The Etymologies of the 1930s (Ety/MBAL), whose Sindarin derivatives would start with bal- conflicting with later forms like S. bal- “✱to have [divine] power” (PE17/131). For purposes of Neo-Sindarin I would use ᴺS. nadh- “to chew, gnaw” from ᴹ√NYAD “gnaw” (Ety/NYAD).
nactha-
verb. bite
nag-
verb. to chew, gnaw
A noun appearing as G. nanc “a bite” in the Gnomish Lexicon of the 1910s (GL/59), clearly based on the early root ᴱ√NAKA “bite” (QL/64).
Neo-Sindarin: Since ᴹ√NAK “bite” appeared in Tolkien’s later writings, I’d retain the noun ᴺS. nanc “bite” for purposes of Neo-Sindarin.