CRT spot, DM display, Doppler signal, IF signal, IM display, RF echoes, accord, acknowledge, acknowledgment, act like, action and reaction, adumbration, affect, agree, agree in opinion, agree with, answer, answer back, answering, antiphon, antiphonal chanting, antiphony, ape, assume, automatic reaction, autonomic reaction, back answer, back talk, backchat, be affected, be in tune, be inspired, be involved, be moved, be reflected, be sent back, beam, beat signal, blips, boom, booming, borrow, bounce back, bounceback, bounces, care about, caring, catch the flame, catch the infection, change color, chime in with, choir, chord, chorus, claviature, close with, coincide, color with emotion, come again, come back, come back at, come up again, comeback, concern, concur, conform to, conformist, console, copier, copy, copycat, copyist, counterfeit, counterfeiter, crib, cuckoo, dig, display, dissembler, dissimulator, ditto, do, do a repeat, do again, do like, do over, double-dot display, double, doubling, duplicate, duplication, echo back, echo signal, echoer, echoist, eighty-eight, empathize with, empathy, emulate, encore, evasive reply, facsimile, fake, faker, fall in with, fellow feeling, fingerboard, flash back, forge, forger, give acknowledgment, give answer, go along with, go back, go like, go with, great, growl, growling, grumble, grumbling, hoke, hoke up, hypocrite, identification, identify with, imitate, imitation, imitator, impersonator, impostor, involvement, iteration, ivories, keep coming, keyboard, keys, local oscillator signal, make like, manual, meet, mime, mimer, mimic, mimicker, mirror, mirror image, mocker, mockingbird, monkey, organ manual, outline, output signal, parrot, pathos, pedals, phony, piano keys, picture, pips, plagiarism, plagiarist, plagiarize, poll-parrot, polly-parrot, polly, poseur, predictable response, quotation, quote, radar signal, react, reaction, reading, ready reply, reappear, reappearance, rebirth, reboation, rebound, receipt, recur, recurrence, redo, redouble, redoubling, reduplicate, reduplication, reecho, reflect, reflection, reflex, reflex action, refluence, reflux, regurgitate, regurgitation, reincarnate, reincarnation, reiteration, rejoin, rejoinder, relate to emotionally, relating, renew, renewal, reoccur, reoccurrence, repartee, repeat, repeat performance, repercussion, repetition, replica, replication, reply, repost, reproduce, reproduction, rescript, rescription, resound, resounding, respond, respondence, response, responsion, responsiveness, responsory, responsory report, resume, resumption, retort, retroaction, return, return answer, return for answer, return signal, reverberate, reverberation, revert, revive, revulsion, ring, riposte, rise, roll, rumble, rumbling, say, say again, say in reply, send back, shadow, share, sharing, sheep, shoot back, short answer, side with, signal, signal display, silhouette, simulate, simulation, simulator, snappy comeback, solo, sound, spot, strike in with, swell, sympathetic chord, sympathetic response, sympathize with, sympathy, talk back, target image, thunder, thundering, trace, transmitter signal, unthinking response, vibes, vibrations, video signal, witty reply, witty retort, yes-and-no answer