Halo
mid 16th century (denoting a circle of light round the sun etc.): from medieval Latin, from Latin halos, from Greek halōs ‘disc of the sun or moon’.
wiktionary
From Latin halōs, from Ancient Greek ἅλως(hálōs, “disk of the sun or moon; ring of light around the sun or moon; threshing floor with its surrounding threshold; disk of a shield”); itself of unknown origin, see هلال and תהילה. Used in English since 1563, sense of light around someone’s head since 1646.
etymonline
halo (n.)
1560s, "ring of light around the sun or moon," from Latin halo (nominative halos), from Greek halos "disk of the sun or moon; ring of light around the sun or moon" (also "disk of a shield"); ""threshing floor; garden," of unknown origin. The sense "threshing floor" (on which oxen trod out a circular path) probably is the original in Greek. The development to "disk" and then to "halo" would be via roundness. Sense of "light around the head of a holy person or deity" first recorded 1640s. As a verb from 1791 (implied in Haloed).
