also: しわし
noun
Obsolete term for a prostitute; not used in modern Japanese. Found only in historical texts.
江戸時代の文献に「私窩子」という語が見られる。
The word 私窩子 appears in documents from the Edo period.
The exact derivation is uncertain; the kanji 私 (private) and 窩 (den, hollow) or 窠 (nest) combine to suggest a hidden or private place, likely referring to a brothel or prostitute's quarters.