A short, sharp or high note or noise, as of a bird or insect.
(radar, sonar, radio telescopy etc.) A pulse of signal whose frequency sweeps through a band of frequencies for the duration of the pulse.
To make a short, sharp, cheerful note, as of small birds or crickets
To speak in a high-pitched staccato
(radar, sonar, radio telescopy etc.) To modify (a pulse of signal) so that it sweeps through a band of frequencies throughout its duration.
To cheer up; to make (someone) happier.