taru-adjective, adverb taking the 'to' particle
tumultuous debate; uproarious argument
Describes a scene where many people are loudly voicing their opinions at once, often in a heated discussion. Used as a たる adjective or with と adverbially.
会議は喧々諤々たる議論になった。
The meeting turned into a tumultuous debate.
参加者たちは喧々諤々と意見を戦わせた。
The participants argued uproariously, each voicing their opinion.
Similar yojijukugo meaning outspoken and frank debate, but without the noisy, chaotic connotation of 喧々諤々.
Also means noisy and tumultuous, but can refer to general uproar, not necessarily limited to debate.
A yojijukugo combining 喧々 (noisy, clamorous) and 諤々 (outspoken, arguing frankly). The exact historical derivation is uncertain, but it is conventionally associated with heated, vocal disputes.