panel: [13] Etymologically, a panel is nothing more than a ‘small pane’. It comes via Old French from Vulgar Latin *pannellus, a diminutive form of Latin pannus ‘rag’ (source of English pane [13]). Both panel and pane entered English with their original ‘cloth’ connotations intact, but they have now virtually died out, surviving only in the compound counterpane (which is actually an alteration of an earlier counterpoint), and ‘shape’ has taken over from ‘substance’ as the word’s key semantic feature. => pane[panel etymology, panel origin, 英语词源]