trill

A trill is a musical ornament consisting of a rapid alternation between the written note and the note above it (the upper neighbor). It is usually begun on the upper neighbor and continued for the duration of the written note, with a number of oscillations that depends on tempo, style, and performer preference. In notation, a trill is commonly marked with the letters “tr” above the note, sometimes accompanied by a wavy line or a termination indication at cadence.

In performance practice, trills may be adjusted to fit stylistic conventions. They are often started on the upper auxiliary, but historical sources show variations where the trill begins on the main note or ends with a cadential ending. Trills are distinct from mordents, which alternate with the lower neighbor. Cadential trills, common near the ends of phrases, may include a specific termination returning to the principal note.

In linguistics, a trill refers to a consonant produced by vibrating the active articulator against a passive one, creating a rapid series of closures. The most familiar example is the alveolar trill [r], as in Spanish or Italian. Other trills include the bilabial trill [B̥], the dental trill, and the uvular trill [ʀ]. Trills vary across languages in their exact articulation, voicing, duration, and energy.

Outside music and phonetics, the term trill can describe any rapid, repeated oscillation of a sound in natural phenomena, such as certain birdsong or insect calls. The primary, technical uses of the term remain in musical ornamentation and consonantal phonetics.