Ad Libitum Law and Legal Definition

Ad Libitum is a Latin term which means “at pleasure” or at the discretion of the performer. The term is generally used as a direction imparting license to alter or omit a part. The term ad libitum is often shortened to "ad lib” which means “at the performers pleasure.” An example showing the usage of the term ad libitum is that a vested property rights cannot be taken away ad libitum by retrospective legislation.