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lugar m. (Noun) "place;" "room"

10th cent. Old Spanish locar. From Late Latin localis 'id.,' from Latin locus "place" (see luego).

Romance: Western Vulgar Latin: Asturian llugar, Portuguese lugar, Galician lugar, Catalan locar, French local
luna f. (Noun) "moon"

10th cent. From Latin luna 'id.' Old Latin losna. From Proto-Italic *louksnā- 'id.' From Proto-Indo-European *leu̯k-s-nh2- "bright." From the root *leu̯k- "to shine" (see luz).

Also the origin of the surname Luna, indicating that the person hailed from one of the towns called Luna (there is one in Zaragoza, Alava, Albacete, and Leon).

Romance: Western Vulgar Latin: Asturian lluna, Portuguese lua, Galician lúa, Catalan lluna, French lune, Italian luna; Eastern Vulgar Latin: Aromanian lunã, Romanian lunã; Sardinian: luna

Indo-European: Celtic: Old Irish lúain "Monday;" Balto-Slavic: Old Prussian lauxnos "stars" Hellenic: Ancient Greek λύχνος (lykhnos) "lamp;" Indo-Iranian: Avestan raoxšna- "light"

At a very late date of Proto-Indo-European in the north-west we see a pre-form *louk-s-neh2- develop meaning "moon." This replaced the older Proto-Indo-European name for the moon based on "to measure" *meh1-, as the month was marked in moons.
luz f. (Noun) "light"

13th cent. From Latin lux 'id.' From Proto-Italic *louk- 'id.' From Proto-Indo-European *leu̯k- "to shine."

Romance: Western Vulgar Latin: Asturian lluza, Portuguese luz, Galician luz, Italian luce; Sardinian: luche

Indo-European: Germanic: Gothic liuhaþ "light," Old Norse ljóss "bright," Old High German lioht "light," Old English lēoht 'id.' (English light); Balto-Slavic: Russian luč "ray," Czech louč "torch," Slovene lúč "light (from a fire)," Old Prussian luckis "torch;" Hellenic: Ancient Greek λευκός (leukós) "light;" Armenian: lowc'anem "to lighten;" Indo-Iranian: Sanskrit rócate "to shine," Young Avestan raocaiia- "to make shine;" Tocharian: A luk- "to shine," B luk- 'id.;' Anatolian: Hittite lukk-tta "to dawn," lukkatt- "dawn"