One who abuses [in the various senses of the verb].(noun)
Gnu Collaboartive International Dictionary of English: licensed under The Code Project Open License (CPOL)
Use "abuser" in a sentence
"When I use the word abuser I'm talking about batterers, both physical and psychological, sexual predators and those who kill the flower of youth with the effluent of inappropriate desire."
"Oh, and it's nice to see that Erik Erickson believes that a person who speaks out against an abuser is a bad parent and attention seeker."
"Child sexual abuse sadly doesn't happen on a small scale when the possible abuser is a person of great influence."