call boy

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun One who tells performers when it is time for them to go on stage.
• noun A bellhop.
• noun A male prostitute who arranges appointments by telephone or computer.

from The Century Dictionary.

• noun A boy whose duty it is to call actors upon the stage at the proper moment.
• noun A boy who repeats the orders of the captain of a steamboat to the engineer.
• noun A boy who answers a call-bell.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Alternative spelling of callboy.