noun
crawl-in entrance; small entrance to a tea ceremony room
A small, low entrance to a traditional Japanese tea ceremony room (chashitsu) through which guests enter on their knees, symbolizing humility and equality.
茶室のにじり口は、身分に関係なく全員が頭を下げて入るために作られた。
The crawl-in entrance of the tea room was designed so that everyone, regardless of status, enters by bowing their head.
From 躙る (にじる, to edge forward on one's knees) + 口 (ぐち, entrance). The spelling 躙 is a kokuji (Japanese-created kanji) combining 足 (foot) and 門 (gate), suggesting the action of inching forward.