What do you call the technique of squeezing three notes into the space normally occupied by two?

The technique of squeezing three notes into the space normally occupied by two is called triplets. This rhythm creates a unique subdivision of the beat, allowing musicians to achieve a flowing, subdivided feel that contrasts with standard note divisions. In a triplet, each note is typically of equal duration, and together they fill the equivalent time of two regular notes of the same value.

Triplets can be found in many musical styles and are often notated with a "3" above or below the group of notes, indicating that three notes should be played in the time usually taken by two. This use of triplets allows for a more intricate and varied rhythmic texture in a piece of music.

Other terms related to rhythm provide context but do not describe the same specific technique. Tuplets encompass a broader category of rhythmic divisions that can include groups of notes beyond three, whereas quartets refer to a group of four musicians or four notes played together, which is unrelated to the triplet concept. Polyrhythm describes the simultaneous use of different rhythms and does not specifically address the grouping of three notes in the space of two.