ᴹ√ESEK root. “*sedge, reed”
A (Ilkorin-only?) root in The Etymologies of the 1930s with the derivatives Ilk. esg “sedge, reed”, Ilk. esgar “reed-bed”, and Ilk. Esgaroth “reed-lake” (Ety/ESEK). Elsewhere it seems S. lisg means “reed” as in S. Lisgardh “Land of Reeds” (UT/34), and similarly ᴹQ. liske < ᴹ✶lisge (PE19/51). Thus I suspect ᴹ√ESEK was a transient idea, one of the etymologies Tolkien considered for Esgaroth.
Reference ✧ Ety/ESEK