a group of people or animals engaged in a task or activity for a period of time and then replaced by a similar group

the wagons were pulled by relays of horses

gangs of workers were sent in relays

an electrical device, typically incorporating an electromagnet, which is activated by a current or signal in one circuit to open or close another circuit

a device to receive, reinforce, and retransmit a radio or television signal

TV transmitters and relay stations

receive and pass on (information or a message)

she intended to relay everything she had learned

lay again or differently

they plan to relay about half a mile of the track