Japanese DictionaryDefinition of 一子相伝
- (n) transmission of the secrets of an art, craft, trade or learning from father to only one child
一子相伝の技と言うわりには、彼の蹴りは大した事はないね。
For a guy who was chosen by his father as the only son to be taught the secrets of this martial art, he doesn't have much of a kick.