The word “polibek”, “a kiss”, comes from the verb “líbat”, “to kiss”, and “líbat”, in turn, is a word that has lots of relatives in related Slavic languages. Most of them have to do with love, and they’re related to other words in Czech like “líbit se”, which usually means “to be appealing or pleasing”, and “líbánky” which means “honeymoon”.
I doubt though that it’s the etymological aspect of kissing that you’re really interested in, and “polibek” is a little more formal. If you want to give or receive a kiss, the word you need (if, indeed, you need a word at all) is “pusa”. “Dej mi pusu”, “give me a kiss”, “dala mu pusu”, “she gave him a kiss”. And as with most things in Czech, kisses come in sizes large and small. Children get and give “pusinky” - little kisses.
But back to sensual etymology, because it really is quite interesting, actually... The word “pusa” is a very old word for a kiss, with cousins in almost every European language from Spain to Sweden to Albania. The day-to-day word for mouth in Czech though, is also “pusa”. So I suppose one could argue that Czechs refer to their mouths as their kissers, thus allowing the nice sentence “dal jí pusu na pusu”, “he gave her a kiss on the mouth”, as the band Jablkoň sings.
And for the older kissers among you, another word for a kiss is the slightly archaic “hubička”, which comes from the word “huba”, or muzzle. A phrase that accompanies this word is “za hubičku” meaning “in exchange for just a little”. “How much will you sell me that old car for?” “Za hubičku”, “for a kiss”.
