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sad sack

1 ENTRIES FOUND:
sad sack noun
plural sad sacks
sad sack
noun
plural sad sacks
Britannica Dictionary definition of SAD SACK
[count] US, informal + old-fashioned
: a person who is not successful or able to do things well : an inept person who causes feelings of pity or disgust in other people

— sad–sack

adjective, always used before a noun