can of worms
noun
Informal.
a source of many unpredictable or unexpected problems: Buying a company we know nothing about would be opening up a whole new can of worms.
Origin of can of worms
First recorded in 1965–70
Words nearby can of worms
camwood,
caméra stylo,
can,
can buoy,
can do with,
can of worms,
can opener,
can tho,
can't,
can't abide,
can't but
Idioms and Phrases with can of worms
can of worms
A complex unexpected problem or unsolvable dilemma, as in Tackling the budget cuts is sure to open a can of worms. This expression alludes to a container of bait used for fishing, which when opened reveals an inextricable tangle of worms. [1920s]