Meaning
Don't tell an expert what they know, it's daft.
Origin
From 18th-century Britain, tied to slang; 'suck eggs' for know, by 1700s in a Swift text for nix. A 1740s tale uses it for a jab.
Variants
- Don't teach
- Suck eggs
Usage Examples
- Don't teach your grandmother to suck eggs; she knows!
- Suck eggs? Don't teach gran.
- Grandma's fine; don't egg her.