chump

Short definition from Wiktionary

Noun

1. 1
   An incompetent person, a blockhead; a loser.
2. 2
   A gullible person; a sucker; someone easily taken advantage of; someone lacking common sense.
3. 3
   The thick end, especially of a piece of wood or of a joint of meat.
4. 4
   A person's head or face.

Verb

1. 1
   To treat (someone) as a chump; to defraud or swindle (someone).
2. 2
   Dated form of chomp.