Gnomish
aith
noun. sword
aith
noun. thorn
aithos
noun. thorn bush
aitheb
adjective. sharp, piercing
aithrog
noun. warrior
aithweg
noun. warrior
aith(i)or
noun. warrior, swordsman
aithl
noun. spring
aithla-
verb. to spring (from), issue forth, bubble up
aitha-
verb. to prick, sting
aithi
noun. sword
aithog
adjective. thorny
aithr
noun. thorn, †sword
aithra
adjective. piercing, sharp; thorny
aithron
noun. warrior, †swordsman
aithwen
noun. sword
aithyl
noun. spring
crisc
adjective. sharp
ectha
noun. sword
ecthor
noun. warrior, swordsman
engan
noun. spear
gothweg
noun. warrior
hairen
feminine name. Spring
tigla-
verb. to prick
tuil
noun. spring
A noun appearing as G. aithos “thorn-bush” in the Gnomish Lexicon of the 1910s, a combination of G. aith “thorn” and G. tath “hedge”, derived from primitive ᴱ✶eχt·taþ· (GL/18). This word also appeared in Gnomish Lexicon Slips modifying that document (PE13/108).
Neo-Sindarin: I would adapt this word as ᴺS. eithos “thorn bush” for purposes of Neo-Sindarin, since the diphthong ai was ei in non-final syllables in Sindarin of the 1950s and 60s. I would re-etymologize this word as a combination of the later words [N.] êg “thorn” (< √EK) and [N.] toss “bush”, where primitive ekt- became eith-.