comeback

squelch

back talk

crack, quip, sally, wisecrack, witticism, zinger

cut, insult, put-down

back talk, banter, persiflage, repartee

acknowledgment (or acknowledgement), comment, communication, correspondence, feedback, non sequitur, observation, reaction, remark

defense, explanation, justification, plea, rebuttal, refutation

resuscitation, revival

survival

come around, come round, come to, improve, pick up, revive

cheer (up), perk (up)

pull through, survive

recruit

reanimate, revitalize, revive

acknowledge, comment, communicate, correspond, react, remark

counter, defend, deny, explain, field, rebut, refute