Meaning of traveling-wave tube

trav'eling-wave' tube"

Pronunciation: (trav'u-ling-wāv', trav'ling-), [key]
— Electronics. Electronics.
  1. an electron tube used in microwave communications systems, having an electron beam directed coaxially through a wire helix to produce amplification.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.