A rapid alternation between two adjacent notes, usually a semitone or tone apart, in music. The pianist executed a perfect trill that added a lively touch to the composition.
A quavering or vibratory sound, especially a rapid alternation of sung or played notes. The bird's trill echoed through the forest, creating a melodious atmosphere.
In phonetics, a consonant sound produced by the rapid vibration of an articulator, such as the rolled "r". The Spanish word "perro" contains a trill that many English speakers find hard to master.