Complete armor or protective covering; or metaphorically, an impressive array or display of something.
From em- (cause to be) + panoply. 'Panoply' comes from Greek 'panoplia' (pan- 'all' + hopla 'weapons'), originally meaning full armor. The em- prefix makes it a verb-like noun.
The root 'panoply' originally meant a full suit of armor in ancient Greece, which is why calling something a 'panoply of colors' means a complete, impressive array—the military origin is hiding in plain sight.
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