What does Gliss mean in music?
In music, a glissando (Italian: [ɡlisˈsando]; plural: glissandi, abbreviated gliss.) is a glide from one pitch to another ( Play (help·info)). It is an Italianized musical term derived from the French glisser, "to glide". In some contexts, it is distinguished from the continuous portamento.
What is it called when you run your fingers down the piano?
A glissando (also known as a gliss in this lazy music industry) is a fast slide across several keys on the keyboard. ... To try a right-hand gliss, put your thumb on a high C note and drag your thumbnail down across the keys very quickly all the way to the bottom of the keyboard.