A verb appearing as G. gwadh- “dwell” in the Gnomish Lexicon of the 1910s with a (deleted) primitive form gu̯ađ (GL/46), likely an allusion to the early root ᴱ√ẆAÐA from the contemporaneous Qenya Lexicon (QL/102). In that document, Tolkien gave the Gnomish form as {gwath- >>} gwar-, however, which might align with the deleted primitive form ᴱ✶gu̯ara- “dwell” from the Gnomish Lexicon (GL/38).
Gnomish
rûtha-
verb. to dwell, remain
(m)bara-
verb. to dwell
gwadh-
verb. to dwell
mara-
verb. to dwell
A verb glossed “dwell, remain” in the Gnomish Lexicon of the 1910s listed below G. rû “dwelling, house” (GL/66), thus likely related to ᴱQ. rú “dwelling, village” derived from the early root ᴱ√RU’U (QL/80).