What is "to pay the piper"

Pay \Pay\, v. t. [imp. & p. p. Paid; p. pr. & vb. n. Paying.] [OE. paien, F. payer, fr. L. pacare to pacify, appease, fr. pax, pacis, peace. See Peace.]

1. To satisfy, or content; specifically, to satisfy (another person) for service rendered, property delivered, etc.; to discharge one's obligation to; to make due return to; to compensate; to remunerate; to recompense; to requite; as, to pay workmen or servants.

   May no penny ale them pay [i. e., satisfy].
   --P. Plowman.

   [She] pays me with disdain.
   --Dryden.

2. Hence, figuratively: To compensate justly; to requite according to merit; to reward; to punish; to retort or retaliate upon.

   For which, or pay me quickly, or I'll pay you.
   --B. Jonson.

3. To discharge, as a debt, demand, or obligation, by giving or doing what is due or required; to deliver the amount or value of to the person to whom it is owing; to discharge a debt by delivering (money owed). ``Pay me that thou owest.''
   --Matt. xviii. 28.

   Have patience with me, and I will pay thee all.
   --Matt. xviii. 26.

   If they pay this tax, they starve.
   --Tennyson.

4. To discharge or fulfill, as a duy; to perform or render duty, as that which has been promised.

   This day have I paid my vows.
   --Prov. vii. 14.

5. To give or offer, without an implied obligation; as, to pay attention; to pay a visit. Not paying me a welcome. --Shak. To pay off.

   1. To make compensation to and discharge; as, to pay off the crew of a ship.

   2. To allow (a thread, cord, etc.) to run off; to unwind.

      To pay one's duty, to render homage, as to a sovereign or other superior.

      To pay out (Naut.), to pass out; hence, to slacken; to allow to run out; as, to pay out more cable. See under Cable.

      To pay the piper, to bear the cost, expense, or trouble.

Piper \Pip"er\, n.

1. (Mus.) One who plays on a pipe, or the like, esp. on a bagpipe. ``The hereditary piper and his sons.''
   --Macaulay.

2. (Zo["o]l.)

   1. A common European gurnard ( Trigla lyra), having a large head, with prominent nasal projection, and with large, sharp, opercular spines.

   2. A sea urchin ( Goniocidaris hystrix) having very long spines, native of both the American and European coasts.

      To pay the piper, to bear the cost, expense, or trouble.