graduated
1. [ adjective ] increasing as the amount taxed increases
Synonyms: proportional
Related terms: progressive
2. [ adjective ] marked with or divided into degrees
Synonyms: calibrated
Examples:

"a calibrated thermometer"

Related terms: calibrate calibrate
3. [ adjective ] decreasing as the amount taxed increases
Related terms: regressive
4. [ adjective ] slowly and smoothly
Synonyms: gradatory gradational
Related terms: gradual
Similar spelling:   graduate
  gradate
  graduation
  graded