嫡嗣[chakushi] legitimate heir
嫡子[chakushi] legitimate child
嫡出子[chakushutsushi] legitimate child
嫡孫[chakuson] eldest son's descendants
嫡男[chakunan] heir

嫡披[chakuhi] confidential letter
嫡流[chakuryuu] lineage of eldest son
廃嫡[haichaku] disinheritance
正嫡[seichaku] legal wife
嫡妻[chakusai] one's legal wife