etude; musical study
A musical piece designed to develop a particular technique. Used in classical music contexts.
from French étude
Chopin's etudes are technically difficult.
study; trial work
In art, a preliminary sketch or practice piece; can also refer to any trial work or exercise.
He painted many studies of landscapes.
improvisational theatre
A theatrical exercise or performance based on improvisation. Less common than the musical or art senses.
We practiced improvisational theatre in the drama club.