I’ve always wondered why letting a cat out of the bag is a bad thing. You’d think that if some feline creature is trapped in a plastic (or non-plastic if you’re in NY) vacuum, it would be a great thing for both the cat and the participants involved to simply let the cat out. Now perhaps the cat is a ferocious, mean animal, or perhaps it’s just a kitty. Where did this idiom come from?

Glad you asked.

Let the cat out of the bag

People used to sell piglets tied in bags for farmers to carry home. A con man might swap the piglet in the sack with a cat, a cheaper animal. So when you let the cat out of the bag, you were exposing the con to everyone

Blood is thicker than water

Now, when we think of this idiom (or axiom) we think of family vs. friends and relationships. However, the saying started as the opposite: “The blood of the covenant is thicker than the water of the womb.” Therefore if you were friends, you were blood brothers, which was far deeper than any familial ties.

Till the cows come home

Cows were often milked in their barns at night, making that task one of the 
last on a farmer’s to-do list. The idiom has been alive since the 14th century, and will last until we see a black and white silhouette, come, you know…

Close but no cigar

Carnivals used to give out cigars rather than big fuzzy teddy bears to the victor. To the victor goes the cigar! These games were not tailored towards kids, as who would let their kid have a 1930 cuban? No, that’s for daddy.

Steal someone’s thunder

In 1704 John Dennis—an unsuccessful playwright—invented a new method of creating the sound of thunder for his play, Appius and Virginia. The play flopped and was closed down but shortly afterwards, a production of Macbeth started in the same theatre using the very same method of creating thunder. It is reported that Dennis went to the theatre to watch a performance of Macbeth and when he saw that they were using his technique, he said, “Damn them! They will not let my play run, but they steal my thunder.”

Fly off the handle

In the days before mass merchandising, poorly fastened axe heads would fly off while they were in use. Surprisingly it has nothing to do with pushing flies off handles—I always was under the impression that this was some red-rover construct.