noun
fast Fourier transform; FFT
Mathematical algorithm for computing the discrete Fourier transform efficiently.
高速フーリエ変換は信号処理で広く使われている。
The fast Fourier transform is widely used in signal processing.
フーリエ変換 is the general Fourier transform, while 高速フーリエ変換 specifically refers to the fast algorithm for computing it.
From English 'fast Fourier transform', combining 高速 (high-speed) and フーリエ変換 (Fourier transform).