The term 'slowing down' can be expressed in two different ways in crosswords: Rallentando (11 letters) and Lentando (8 letters). Rallentando is an Italian musical term that means to slow down the tempo of a piece of music. Lentando is a Spanish musical term that also means to slow down the tempo of a piece of music. Both terms are used to describe the process of slowing down the tempo of a piece of music.