プログレッシブ和英中辞典(第4版)の解説
くちづたえ【口伝え】
〔口碑〕an oral tradition；〔口頭〕transmission by word of mouth；〔口授〕oral instruction
爆発のうわさが口伝えに広まった
A rumor that there had been an explosion spread far and wide (by word of mouth).
口伝えで７時に駅に集合という指示が全員に出た
We all received oral instructions to meet at the station at seven o'clock.