Anacrusis

An anacrusis (also called a ‘pickup’ or ‘upbeat’) is one or more notes preceding the first complete measure of a piece or phrase. The anacrusis leads into the downbeat of the first full measure, providing a sense of musical preparation and forward motion.

Many pieces begin with an anacrusis. The opening of ‘Happy Birthday’ has a two-note anacrusis (‘Happy’) that leads into the downbeat (‘BIRTH-day’). Beethoven’s Fifth Symphony famously begins with an anacrusis — three eighth notes leading into a held downbeat (‘Short-short-short-LONG’).

The anacrusis is essentially a phrase-level device. It frames the first downbeat as an arrival, establishing rhythmic expectation. Phrases throughout a piece may also begin with anacruses, with each new phrase entering with a pickup that leads into its first downbeat.

Greek, ‘striking up’, from anakrouein (‘to push back, strike up’).

Treat the anacrusis as upbeat, not downbeat. The energy is leading toward the first complete measure’s downbeat; don’t emphasize the anacrusis itself.