Kisasa - Kisasa

… [Yoshiharu Iijima]
[Lice and humans]
Lice are said to be a corrupted form of the word "shiramushi" (white bug). Their ancient name was "kisasa," and from the character "虱" they were also called "hanpuushi." Furthermore, from Yokoi Ariyu's "Hyakuchu-fu" it is said that they were also called "Thousand-Armed Kannon" (a valiant mercenary), and during the period of their great infestation after World War II, they were slang-like called "white chiichii."

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

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…【飯島 吉晴】
［シラミと人間］
　シラミは白虫（しらむし）の転訛（てんか）であるという。古名はまたキササ，その字〈虱〉から半風子（はんぷうし）とも称する。さらにその形から千手観音という異称もあったことが横井也有の《百虫譜》などにも見え，第2次大戦後の大発生期には隠語風にホワイトチイチイと呼ばれた。…

※「キササ」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