What does trill mean in music?

In music, a trill is a musical ornament involving the rapid alternation of two adjacent notes, resulting in a vibrato-like effect. It is typically indicated by the abbreviation "tr" or "~" placed above or below the affected note. The trill starts on the main note and then quickly alternates between that note and the note above it before resolving back to the main note. The speed of the trill can vary, but it is usually performed quite quickly.

It is commonly used in both classical and popular music and can be applied to many types of instruments, including string instruments, woodwinds, brass instruments, and voices.