Archenemy

The Fourth Doctor noted to be his "sworn archenemy". (TV: The Deadly Assassin) Amy Pond identified the Daleks as the Eleventh Doctor's archenemies. (TV: Victory of the Daleks)

Behind the scenes

 * The Ninth Doctor deemed his upcoming marriage to Emma to be news even his archenemy, the Master, needed to hear. (NOTVALID: The Curse of Fatal Death)