A noun appearing as N. lhâf “lick” (with Noldorin infinitive form lhebi) in The Etymologies of the 1930s from the root ᴹ√LAB of the same meaning (Ety/LAB) where the initial initial l was unvoiced to lh as was the case in Noldorin of the 1930s.
Conceptual Development: This verb was G. lav- “lick” in the Gnomish Lexicon of the 1910s (GL/53), clearly based on the early root ᴱ√LAVA since the unvoicing of initial l was not a feature of Gnomish in the 1910s.
Neo-Sindarin: Most Neo-Sindarin writers adapt this word as ᴺS. lav- “to lick” since the unvoicing of initial l was also not a feature of Sindarin in the 1950s and 60s.
The Etymologies seem to list this word as a noun, but it is clearly the third person singular of the verb