姻戚[inseki] relative by marriage
遠戚[enseki] distant relative
外戚[gaiseki] maternal relative
休戚[kyuuseki] weal and woe
親戚[shinseki] relative

親戚知己[shinsekichiki] relatives and acquaintances
憂戚[yuuseki] grief
縁戚[enseki] relative
親戚関係[shinsekikankei] relations
親戚眷属[shinsekikenzoku] one's family and relatives

育ての親[sodatenooya] foster parents
育て親[sodateoya] foster parent
１等親[ittoushin] first-degree relative
仮親[karioya] adopted parents
近親[kinshin] near relative

近親婚[kinshinkon] consanguineous marriage
近親相姦[kinshinsoukan] incest
懇親[konshin] friendship
懇親会[konshinkai] friendly reunion
似非親[eseoya] distant disinterested parent