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
bara
noun. home, cottage
bara dhair haithin
place name. Cottage of the Lost Play
(m)bara-
verb. to dwell
bar(n)a-
verb. to dwell in (a land), till (land)
baron
adverb. from home, out, away, abroad
mara-
verb. to dwell
barog
adverb. from home, out, away, abroad
gwadh-
verb. to dwell
mavrog
adjective. eager
A verb appearing as G. {bartha- >>} bara- or barna- “dwell in, till (tr.)” in the Gnomish Lexicon of the 1910s (GL/21), clearly derived from the early root ᴱ√MBARA “dwell, live” (QL/63). Its gloss is followed by a parenthentical comment “(land)”. Likely the original sense was “dwell in (a land)”, and from there it gained the sense “✱prepare a land for dwelling” = “till (land), ✱cultivate”.
Neo-Sindarin: Since √MBAR continues to appear in Tolkien’s later writings, for purposes of Neo-Sindarin I would retain transitive ᴺS. barna- “to till (land), ✱cultivate” with an original sense “to dwell in (a land)”. Given this verb’s association with cultivation, however, I would use the later verb [N.] dortha- as the primary verb for “to dwell, stay, settle, ✱live (in a place)” (Ety/NDOR).