Brown noise; Brownian noise
Physics term for a signal or process with a power spectral density inversely proportional to frequency squared. Named after Brownian motion, not the color brown.
See also: ブラウン運動
Brown noise is a type of noise with strong low-frequency components.
Variant with interpunct; less common but seen in technical contexts.
From English 'Brown noise', named after Robert Brown and his discovery of Brownian motion.