The term 'smallest degree' can be defined as the LEAST amount or magnitude of something. It is often used to describe the smallest unit of measurement, such as degrees in a temperature scale or angles in a circle. In the context of a crossword puzzle, the term 'smallest degree' could refer to the answer to a clue that requires the LEAST amount of letters. In this case, the solution to the crossword puzzle is the word 'LEAST' which has five letters.