A scoundrel, rascal or unprincipled, deceitful, and unreliable person.

A mischievous scamp.

A vagrant.

(computing) Deceitful software pretending to be anti-spyware, but in fact being malicious software itself.

An aggressive animal separate from the herd, especially an elephant.

A plant that shows some undesirable variation.

(role-playing games) A character class focusing on stealthy conduct.

(horticulture) To cull; to destroy plants not meeting a required standard, especially when saving seed, rogue or unwanted plants are removed before pollination.

(of an animal, especially an elephant) Vicious and solitary.

(by extension) Large, destructive and unpredictable.

(by extension) Deceitful, unprincipled.

Mischievous, unpredictable.