ad valorem: Meaning and Definition of

ad va•lo•rem

Pronunciation: (ad vu-lôr'um, -lōr'-), [key]
  1. in proportion to the value (used esp. of duties on imports that are fixed at a percentage of the value as stated on the invoice).
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.