A group of samples organized in a musically relevant way. For example, most piano samples are actually made up of many different samples. There are usually at least 8 (sometimes many more) different samples across the keyboard, and in many cases there are samples of different velocities and so on. This is necessary due to how sensitive our ears are to timbral changes that result when sampled audio is pitched up or down. Similarly, our ears usually reveal to us many other things about a performance. You can record a sample of a hard piano strike and play it back at a low volume, perhaps even with a filter on it to limit the high frequencies, but our ears can still tell something isn’t right. Therefore the sounds that we consider good or believable in sampling instruments are usually made up of many samples combined together to more closely approach the original instrument. Once these sounds are tied together they become known as a multi-sample. The exact terminology used by your instrument may vary, but multi-sample is the most commonly used term.