Prompter

noun
1.
a person or thing that prompts.
2.
Theater. a person who is offstage and follows a play in progress from the book, repeating missed cues and supplying actors with forgotten lines.
3.
an electronic or mechanical device for prompting a speaker or performer.
adjective, prompter, promptest.
1.
done, performed, delivered, etc., at once or without delay:
a prompt reply.
2.
ready in action; quick to act as occasion demands.
3.
quick or alert:
prompt to take offense.
4.
punctual.
verb (used with object)
5.
to move or induce to action:
What prompted you to say that?
6.
to occasion or incite; inspire:
What prompted his resignation?
7.
to assist (a person speaking) by suggesting something to be said.
8.
Theater. to supply (an actor, singer, etc.) from offstage with a missed cue or forgotten line.
verb (used without object)
9.
Theater. to supply forgotten lines, lyrics, or the like to an actor, singer, etc.
noun
10.
Commerce.

a limit of time given for payment for merchandise purchased, the limit being stated on a note of reminder (prompt note)
the contract setting the time limit.

11.
the act of prompting.
12.
something serving to suggest or remind.
13.
Computers. a message or symbol from a computer system to a user, generally appearing on a display screen, requesting more information or indicating that the system is ready for user instructions.
Idioms
14.
take a prompt, (in acting) to move or speak in response to a cue.
noun
1.
a person offstage who reminds the actors of forgotten lines or cues
2.
a person, thing, etc, that prompts
adjective
1.
performed or executed without delay
2.
quick or ready to act or respond
adverb
3.
(informal) punctually
verb
4.
(transitive) to urge (someone to do something)
5.
to remind (an actor, singer, etc) of lines forgotten during a performance
6.
(transitive) to refresh the memory of
7.
(transitive) to give rise to by suggestion: his affairs will prompt discussion
noun
8.
(commerce)

the time limit allowed for payment of the debt incurred by purchasing goods or services on credit
the contract specifying this time limit
Also called prompt note. a memorandum sent to a purchaser to remind him of the time limit and the sum due

9.
the act of prompting
10.
anything that serves to remind
11.
an aid to the operator of a computer in the form of a question or statement that appears on the screen showing that the equipment is ready to proceed and indicating the options available