If you call someone who you like a chump, you are telling them that they have done something rather stupid or foolish, or that they are always doing stupid things.
[informal, disapproval]
The guy's a chump. I could do a better job myself.
chump in British English1
(tʃʌmp)
noun
1. informal
a stupid person
2.
a thick heavy block of wood
3.
a.
the thick blunt end of anything, esp of a piece of meat
b.
(as modifier)
a chump chop
4. British slang
the head (esp in the phrase off one's chump)
Word origin
C18: perhaps a blend of chunk and lump1
chump in British English2
(tʃʌmp)
verb
a less common word for chomp
chump in American English
(tʃʌmp)
noun
1.
a heavy block of wood
2. Informal
a foolish, stupid, or gullible person; dupe or fool