Rare literary term for sexual desire or lust; cross-referenced with 性欲. Not used in everyday conversation.
See also: 性欲
In old novels, the word 淫気 is sometimes used to express sexual desire.
Compound of 淫 (いん, 'lewd, licentious') and 気 (き, 'spirit, mood, feeling'). The exact historical derivation is uncertain; the word is rare and literary.