alteration

/ˌȯl-tə-ˈrā-shən/

Middle English alteracioun "change, transformation," borrowed from Anglo-French & Medieval Latin; Anglo-French alteracion, borrowed from Medieval Latin alterātiōn-, alterātiō, from Late Latin alterāre "to change, alter-tiōn-, -tiō, suffix of verbal action

noun

  1. the act or process of altering something : the state of being altered

  2. the result of changing or altering something: such as

  3. a change made in fitting a garment

The dress needs alteration for a proper fit.