Etymology of brilliant

Brilliant comes from the French brilliant (sparkling, shining) from the Italian brillare (sparkle, whirl), from the Latin berillare (to shine like a beryl), from berillus (beryl, precious stone), from the Latin beryllus, which is a transliteration of the Greek beryllos [beryl, precious stone; Gr: βήρυλλος].
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In modern Greek:
a) beryllos (or better pronounced as viryllos): beryl [Gr: βήρυλλος]
b) beryllio: beryllium (Be) [Gr: βηρύλλιο]
c) brilanti (or brigianti): diampond, brilliant [Gr: μπριλάντι]
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Fr: briller, brillantine, brillant; It: brillare; Grm: Brillant, Brille

OED
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