pig in a poke

Meaning

Noun

• Something whose true value is concealed or unknown and may be lower than expected by the buyer or claimed by the seller, especially something offered for sale.

Origin

• Reportedly from the practice of substituting a butchered cat, etc. for a suckling pig when sold in a sack at a market. Other theories circulate but all involve the purchase of a cat in a bag, where the buyer expected better.