red-light district; pleasure quarters
Refers to the world of geisha, courtesans, and entertainment districts, especially in historical or traditional contexts. Often associated with 花柳界.
See also: 花柳界 (かりゅうかい)
He is knowledgeable about the pleasure quarters.
Used for romantic entanglements, often with a nuance of sophistication or involvement in the pleasure quarters. Less common than the district sense.
粋筋のしきたりは複雑だ。
The customs of the red-light district are complex.
The incident arose from a tangled love affair.
Compound of 粋 (いき, 'chic, stylish') and 筋 (すじ, 'line, lineage, quarter'). The exact historical derivation is uncertain, but it likely originated as a term for the stylish world of the pleasure districts.