(Internet) reply; response (to an electronic message)

(Internet) to reply; to respond

(colloquial) -less

(euphemistic) sexless, having no sexual activity for a long time (between a married couple)

to come back, to return, to go back to

to return, go back / to move in the opposite direction / to interchange front and back / to change color, fade / (of a year) to renew / (by extension) to start over / to [verb] completely

(Internet slang) replying instantly; instant reply

careless mistake

sundress

(information theory) lossless