to give the password―give the watchword―make a countersign 合言葉を言う - 斎藤和英大辞典
(a) sign and countersign 合い言葉 《「山」といえば「川」など》. - 研究社 新英和中辞典
You must countersign on this line of the contract
この契約の条項に副署しなくてはならない - 日本語WordNet
to countersign a document signed by the Emperor as required under the laws of the former Meiji Constitution of Japan
(大臣が)天皇の署名に副えて署名する - EDR日英対訳辞書
Sign and a countersign. (The sort where you reply "River" to "Mountain").
合言葉(「山」といえば「川」と答える類)。 - Tanaka Corpus
COUNTERSIGN COLLISION DETECTION CIRCUIT FOR WIRELESS INTERROGATOR 無線式質問器の応答信号衝突検出回路 - 特許庁
To provide a countersign collision diction circuit for obtaining a wireless interrogator that is small, light and inexpensive and also the wireless interrogator including the countersign collision detection circuit. 小型軽量で安価な無線式質問器を得るための応答信号衝突検出回路、またその応答信号衝突検出回路を組み込んだ無線式質問器を提供する。 - 特許庁
On this occasion, the rule that each minister could countersign laws and so forth by him or herself was abolished, and it was decided that all Imperial edicts had to be countersigned by the Prime Minister.
その際、各省大臣の単独副署の制度が廃止され、全ての勅令に内閣総理大臣が副署することになった。 - Wikipedia日英京都関連文書対訳コーパス