the line, "'Kiss'? What is 'kiss'?"-- emblematic of campy interplanetary romance, which of course is invariably between a male human and a female alien. (It was a favorite catchphrase of the crew on Mystery Science Theater 3000.) The line is often attributed to Altaira (Anne Francis) in The Forbidden Planet (1956) or to one of Kirk's conquests in the original series of Star Trek. This was investigated on the rec.arts.sf.tv newsgroup, and they've ruled out The Forbidden Planet and Star Trek.
It's probably just a spurious quotation, along the lines of "Play it again, Sam" or "Judy, Judy, Judy" (or for that matter "Beam me up, Scotty"). Star Trek did, however, have many "What is 'X'?" scenes, most notoriously in the episode "Spock's Brain", which had the immortal line, "'Brain' and 'brain'! What is 'brain'?"
Zimmer also supplied a partial transcript of another episode featuring cross-planetary misunderstanding, "The Apple", in which an alien asks "What is love?" and, on understanding that holding and touching are involved, announces: "Vaal has forbidden this."
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