1.
in unison, with one voice, unanimously
Everyone saying the same thing, expressing the same opinion.
全員が異口同音に賛成した。
Everyone agreed in unison.
異口同音に「素晴らしい」と言った。
They all said "wonderful" with one voice.
参加者たちは異口同音に不満を述べた。
The participants unanimously expressed their dissatisfaction.
A 四字熟語 (four-character idiom) meaning 'with one voice' or 'unanimously.'
ETYMOLOGY:
異口 (different mouths) + 同音 (same sound) — many people with different mouths all saying the same thing.
COMMON PATTERNS:
- 異口同音に: unanimously, with one voice (adverbial use)
- 異口同音に言う: to say with one voice
- 異口同音に賛成する: to unanimously agree
USAGE:
Somewhat literary/formal. Used in writing and formal speech more than casual conversation. Emphasizes that multiple people independently expressed the same opinion or reaction.
SIMILAR EXPRESSIONS:
- 口を揃えて: in unison (more everyday)
- 満場一致: unanimous (formal, used for votes/decisions)