cost a pretty penny
idiom

- to be expensive; to cost a lot of money

(McGraw-Hill Dictionary)

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If something is expensive when it costs a pretty penny, does that mean it's cheap if it costs an ugly penny? Not really.

In the expression "cost a pretty penny," pretty has nothing to do with beauty. It simply means "a lot" or "very". This usage that goes way back to the 15th century. Some typical, modern examples:

"He was pretty annoyed", "They were pretty impressed with the candidate", "That was a pretty amazing presentation".

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Other PENNY phrases that you may hear or read include:

- a penny for your thoughts? = something that you say in order to ask someone who is being very quiet what they are thinking about ("A penny for your thoughts?"... "Sorry, I was just thinking about our upcoming holiday.")

- pinch pennies = to be thrifty, miserly (I had to pinch pennies when I was in college)

- a bad penny = a worthless person (I wouldn't talk to him if I were you. He's a bad penny.)

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SYNONYMS

costly, expensive, pricey, steep, it cost an arm and a leg

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Practice OWAD in a conversation:

"Ordering wine in up-market restaurants can really cost A PRETTY PENNY."