Wikipedia
Bandlimiting
Bandlimiting is the limiting of a signal's Fourier transform or power spectral density to zero above a certain finite frequency. A band-limited signal is one whose Fourier transform or power spectral density has bounded support.
The signal may be either random ( stochastic) or non-random ( deterministic).
In general, infinitely many terms are required in a continuous Fourier series representation, but if a finite number of Fourier series terms can be calculated from that signal, that signal is considered to be band-limited.