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(saying) with one voice; unanimously; in chorus; in unison; as one
全員が異口同音に賛成を唱えた。
Everyone voiced approval in unison.
異口同音に反対意見が出された。
Objections were raised with one voice.
住民たちは異口同音に安全を訴えた。
The residents unanimously appealed for safety.