Definition: To buy something sight unseen.
Origin
Seems I couldn’t fool you with this one. Many Pig Players wrote in with the correct answer. It’s hard to believe, but some merchants from time immemorial have been shady and out for a quick buck, which never happens nowadays, of course. Times were tough back then. What would you do? You’ve got a pig that’s not looking too pink and rosy, but you want to make a quick deal. Put it in a sack, or poke, of course. The next trick is to convince your naive pig buyer not to open the bag until he gets home and you’ve tucked the ill-gotten booty under your straw mattress. Squiggly little pigs that are difficult to catch if they get loose sounds like a good excuse. Yeah, that’s the ticket.
A special applause goes to Lin_Duh who came up with the fact that “let the cat out of the bag” is connected with this phrase. Sometimes the pig was actually a cat — imagine that.
