榫卯 Traditional form: 榫卯 Pinyin (reading): sǔnmǎo Definitions: mortise and tenon Characters: 榫 - mortise and tenon; to fit into 卯 - 4th terrestrial branch; period from 5-7 a.m. Traditional characters: 榫 - mortise and tenon; to fit into 卯 - 4th terrestrial branch; period from 5-7 a.m.