noun, na-adjective
licentiousness; lewdness; sexual indulgence
Refers to excessive or immoral sexual behavior; often used in formal or literary contexts. Can function as a noun or adjectival noun (e.g., 淫な行為).
彼は淫にふける生活を送っていた。
He led a life of licentiousness.
その小説には淫な描写が多く含まれている。
That novel contains many lewd descriptions.
The kanji 淫 originally depicted water overflowing, which came to represent excess, and by extension, excessive sexual desire. The variant 婬 is a later form with the woman radical, emphasizing the sexual connotation.