'widely-discussed' originates from the adverb 'widely' and the past participle 'discussed'. 'widely' derives from Old English 'wīd' (meaning 'broad, wide') with the adverbial suffix '-ly'. 'discussed' comes from Latin 'discutere' via Old French 'discuter', where 'dis-' meant 'apart' and 'quatere/quatere' (or 'cutere') meant 'to shake or strike'.

'discuss' changed from Latin 'discutere' into Old French 'discuter' and Middle English forms before becoming the modern English verb 'discuss'; 'wide' comes from Old English 'wīd' and gained the adverbial suffix '-ly' in later English to form 'widely'. These elements combined in modern English to create the compound adjective 'widely-discussed' (also written 'widely discussed').

Initially, the Latin root carried the sense 'to shake apart, examine'; over time the sense shifted toward 'examine by talking' and then to 'talk about' or 'debate'. 'Widely' kept the core sense 'in a broad or extensive manner', so the compound evolved to mean 'talked about broadly'.