Home > Baker's Student Encyclopedia of Music > Ad Libitum

(Lat., at will; abbr. ad. lib.; Ger. Nachgefallen). 1. Employ the tempo or expression freely. 2. An indication that a vocal or instrumental part may be left out. Cadenza ad libitum, a cadenza that may be performed or not, or may have another substituted for it or improvised, at the performer's will.