A noun appearing as G. nabos “seizure” in the Gnomish Lexicon of the 1910s, a noun form of G. nab- “take, lay hold of”; compare also G. naptha- “seize” (GL/59). It was followed by an oth in parenthesis, probably indicating an alternate form or [nab]oth.
Neo-Sindarin: Since I retain ᴺS. nab- “take, lay hold of” for purposes of Neo-Sindarin, I would adapt this noun as ᴺS. nabas “seizure” = “✱act of taking”.
A verb appearing as G. nab- “take, lay hold of” in the Gnomish Lexicon of the 1910s (GL/59), apparently derived from the early root ᴱ√NAPA which was a variant of ᴱ√MAPA “seize” (QL/59, 64). Its past form nôbi appeared in the untranslated phrase G. nôbi i·mab ’len suila ontha from the contemporaneous Gnomish Grammar, apparently “✱he took the slender hand of his daughter” (GG/11).
Neo-Sindarin: Since √NAP appears in Tolkien’s later writings with glosses like “grasp, seize quickly” (VT47/20), “take hold” (VT47/27), and “take, pick up” (VT47/28), I would retain ᴺS. nab- “to take, lay hold of” for purposes of Neo-Sindarin.