D defs.my
Entry 2 senses Webster, 1913

Betterment

/bĕt'-ẽrm-ənt/ · Bet·ter·ment · IPA /ˈbɛtɚmənt/
01 n. A making better; amendment; improvement.
  1. 1.
    A making better; amendment; improvement.
  2. 2.
    An improvement of an estate which renders it better than mere repairing would do; -- generally used in the plural.(Law) [U. S.]