The headword is the neuter nominative/vocative/accusative plural of the adjective flo/geos, -a, -on; see LSJ s.v. It is extracted from Homer, Iliad 5.745 (web address 1), repeated 8.389: Athena, ready for battle on behalf of the Achaeans, steps onto Hera's fire-bright chariot.
[1] The gloss is the neuter nominative/vocative/accusative plural (as well as the feminine nominative/vocative singular) of the adjective lampro/s, -a/, -o/n, brilliant, radiant, glowing; see LSJ s.v. The headword is glossed likewise in Hesychius, the Synagoge, Photius' Lexicon, Etymologicum Genuinum, and Etymologicum Magnum (796.27); cf. also the scholia to Homer, Iliad 5.745 (above).
[2] The quoted excerpt is from Orestes' fanciful description of his own funeral pyre to Pylades and the Paedagogus, an element of their deception of Electra and Clytemnestra, at Sophocles, Electra 58 (web address 2); cf. omega 35 and tau 718.
[3] With the diphthong, this is an alternative; cf. ps.-Zonaras 1814.14 and 1815.7 (Tittmann). Adler notes that corrected editions of mss GVM supply flo/gios instead. Adler also cites Ambrosian Lexicon 372. Note that *flogi/os, with accent on the penult, was an Argonaut who joined the expedition of Herakles against the Amazons; cf. Apollonius Rhodius, Argonautica 2.956.