unilineal descent

…There are two types of descent that can be traced unilineally: the type that traces descent through the father is called patrilineal descent, and the type that traces descent through the mother is called matrilineal descent. There is also a type of unilineal descent called double unilineal descent, which combines patrilineal and matrilineal descent, and indicates a type of descent in which one belongs to both the father's and mother's groups or categories by tracing patrilineal descent from the father and matrilineal descent from the mother. All theories of descent accept that descent can be traced unilineally and that there can be three types of social processes of descent with two modes of transmission, but there is no consensus on whether other modes or types are acceptable due to differences in theoretical foundations, and researchers also differ in their views on the establishment of modes and types. …

*Some of the terminology explanations that mention "unilineal descent" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…出自が単系的にたどられる様式には2種あり，父親を通じ出自がたどられる様式および型を父系出自patrilineal descentといい，母親を通じてたどられる様式および型を母系出自matrilineal descentという。さらに単系性の型として二重単系出自double unilineal descentがあるが，この型は父系出自の様式と母系出自の様式とを併用した型であり，父親からは父系出自をたどり母親からは母系出自をたどることによって，父親･母親双方の集団やカテゴリーに両属する状態の出自の型を示す。　出自が単系的にたどられ，2様式の伝達様式をもって三つの出自の社会過程の型がありうることは，いかなる出自論においても承認されているが，それ以外の様式や型を認めるか否かについては理論的立脚点の相違によって見解の一致をみておらず，様式や型の設定に関しても研究者の見解にちがいがある。…

※「unilineal descent」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報