ambar (1) ("a-mbar") noun "oikumenē [Greek: the earth as the human habitation], Earth, world" (MBAR), stem ambar- (PE17:66), related to and associated with mar "home, dwelling" (VT45:33); in VT46:13 the latter glosses are possibly also ascribed to the word ambar itself (the wording is not clear). The form ambaren also listed in the Etymologies was presumably intended as the genitive singular at the time of writing (in LotR-style Quenya it would rather be the dative singular); in the printed version in LR, the misreading "ambaron" appears (see VT45:33). Ambar-metta noun "the end of the world" (EO); spelt ambarmetta in VT44:36. The element #umbar in Tarumbar "King of the World" (q.v.) would seem to be a variant of ambar, just like ambar #2 "doom" also alternates with umbar (see below).
Quenya
ambaron
g.sg. ambarónen
ambar
a-mbar
mar
earth
mar (1) noun "earth" (world), also "home, dwelling, mansion". Stem mard- (VT46:13, PE17:64), also seen in the ablative Mardello "from earth" (FS); the word is used with a more limited sense in oromardi "high halls" (sg. oromar, PM17:64), referring to the dwellings of Manwë and Varda on Mt. Taniquetil (Nam, RGEO:66). The initial element of Mardorunando (q.v.) may be the genitive mardo (distinguish mardo "dweller"). May be more or less identical to már "home, house, dwelling" (of persons or peoples; in names like Val(i)mar, Vinyamar, Mar-nu-Falmar, Mardil) (SA:bar, VT45:33, VT47:6). Már is however unlikely to have the stem-form mard-; a "Qenya" genitive maren appears in the phrase hon-maren, q.v., suggesting that its stem is mar-. A possible convention could therefore be to use már (mar-) for "home, house" (also when = household, family as in Mardil, q.v.), whereas mar (mard-) is used for for "earth, world". Early "Qenya" has mar (mas-) "dwelling of men, the Earth, -land" (LT1:251); notice that in LotR-style Quenya, a word in -r cannot have a stem-form in -s-.
cemi
earth, soil, land
cemi noun "earth, soil, land"; Cémi ("k")"Mother Earth" (LT1:257; the "Qenya" word cemi would correspond to cemen in LotR-style Quenya)
kemen
earth
kemen noun "earth"; see cemen.
ambaron (ambarón- as in "g.sg. ambarónen", in LotR-style Quenya this would be a dative singular) noun "uprising, sunrise, Orient" (AM2). - In the Etymologies as printed in LR, the form ambaron also appears in the entry MBAR, but according to VT45:33 this is an error for ambaren, apparently intended as the genitive singular of ambar (in LotR-style Quenya it would rather be the dative singular).