'gaudily-displayed' is a modern English compound combining the adverb 'gaudily' and the past participle 'displayed'. 'Gaudily' derives from the adjective 'gaudy', which ultimately comes from Latin 'gaudium' (via Old French and Middle English), where 'gaudium' meant 'joy'. 'Displayed' comes from Old French 'despleier/ desployer' (to unfold or spread out), formed from Latin elements including 'dis-' and root 'plicare' meaning 'to fold'.

'gaudily-displayed' formed in Modern English by combining 'gaudily' (from Middle English/Old French forms of 'gaudy' influenced by Latin 'gaudium') with 'displayed' (from Old French 'despleier'/'desployer', itself from Latin roots meaning 'to fold/unfold'), resulting in the current compound expression used to describe something shown in a showy manner.

Initially, 'gaudy' had senses tied to festivity or joy ('bright, showy' in a celebratory sense) and 'display' originally carried the sense 'to unfold or spread out'; over time 'gaudy' shifted toward a negative sense of tasteless showiness and 'display' shifted to the general sense 'to show', producing the modern sense 'shown in a tastelessly showy way'.