A noun with variants marol and mara in the Gnomish Lexicon of the 1910s glossed “sand”, probably a derivative of the root ᴱ√MARA (GL/56); see the entry on the root for further discussion. In later writings, Tolkien used N. lith for “sand”.
Gnomish
lith-
verb. to go, depart, be over, finish, end, die
mara
noun. sand
marol
noun. sand
thith
noun. dust
A noun in the Gnomish Lexicon of the 1910s glossed “dust”, appearing below other forms like G. thisin “parched, withered” (GL/73). The latter is clearly a cognate of ᴱQ. sisin from the contemporaneous Qenya Lexicon, and hence is derived from the root ᴱ√SISI as it appeared in that document (QL/84), though its Gnomish derivatives make it clear the actual root was ✱ᴱ√ÞISI.
A verb in the Gnomish Lexicon of the 1910s glossed “go, depart, be over, finish, end, die” (GL/54). The early root ᴱ√lith- also seems to have been related to time (see G. laith “time, the course of time”), so the meaning of this verb may have originally been exclusively temporal, only later spatial.