I know we've had this conversation before. 

There is on screen evidence that Klingons kiss. 

And as someone who was translating a text that needed to clearly distinguish between kissing and biting, the lack of a verb "to kiss" has been rather frustrating. 

I'd prefer multiple verbs, 

To kiss romantically / sexually 

To kiss as friends

To kiss family 

But I'll settle for one, standard (not slang) verb.