Meaning
To raise a topic or take an action that unleashes a tangle of further problems nobody can control, especially by starting to investigate something messy. Usually a warning against doing so; the noun 'a can of worms' also stands alone for the mess itself. Informal, cautionary and faintly comic; heavily used, some would say overused, in journalism. Regional use: American English.
Origin
Twentieth-century American. The image is the angler's bait can of live worms: once the lid is off, the wriggling contents are nearly impossible to gather in again, which is the picture Etymonline uses in dating the figurative 'can of worms' for a difficult problem to 1951. Michael Quinion's World Wide Words documents the literal object in print from 1914 (Leona Dalrymple's novel Diane of the Green Van) and locates the earliest figurative use he could find in 1951, in Michigan's Ironwood Daily Globe, which called a Middle East defence question at Eisenhower's SHAPE headquarters 'a can of worms'. No individual coiner is known; the phrase spread through American journalism from the 1960s, and parallels with Pandora's box are incidental rather than a source.
Research Sources
References used to check this entry’s meaning, history, or documented forms.
Variants
- a can of worms
- a different can of worms
- a whole other can of worms
- opening up a can of worms
Usage Examples
- Asking about the inheritance opened a can of worms at the family reunion.
- Renaming those streets would open a can of worms with every emergency service in the county.
- The 2016 memo was a can of worms nobody in HR wanted to reopen.