arm and a leg

an arm and a leg

slang A lot of money. College tuitions cost an arm and leg nowadays. I'm sick of paying an arm and a leg for rent in this town.
See also: and, arm, leg
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

arm and a leg

An exorbitant amount of money, as in These resort hotels charge an arm and a leg for a decent meal, or Fixing the car is going to cost an arm and a leg. According to Eric Partridge, this hyperbolic idiom, which is always used in conjunction with verbs such as "cost," "charge," or "pay," and became widely known from the 1930s on, probably came from the 19th-century American criminal slang phrase, if it takes a leg (that is, even at the cost of a leg), to express desperate determination.
See also: and, arm, leg
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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References in periodicals archive ?
OK, the studios behind these series (often belonging to the same conglom as the network) spent an arm and a leg on this season's pilots ($5 million-$6 million in some cases) but network license fees are still relatively stable at about $2 million.