degrade

Concise Oxford English Dictionary © 2008 Oxford University Press:
degrade/dɪˈɡreɪd/

▶verb

• 1 cause to suffer a severe loss of dignity or respect; demean.

  ■ lower the character or quality of.

  ■ archaic reduce to a lower rank, especially as a punishment.

• 2 cause to break down or deteriorate chemically.

  ■ Physics reduce (energy) to a less readily convertible form.

– derivatives
degradability noun,
degradable adjective,
degradative adjective,
degrader noun.

– origin ME: from OFr. degrader, from eccles. L. degradare, from de- ‘down’ + L. gradus ‘grade’.