Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio.
a telephone with a speaker and microphone that enables more than one person to take part in a call
Used by arrangement with John Wiley & Sons, Inc.
The American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
A telephone or telephone attachment that contains both a loudspeaker and a microphone, allowing several persons to participate in a call at the same time without the telephone receiver being held.