From Longman Dictionary of Contemporary Englishsmoochsmooch /smuːtʃ/ verb [intransitive + with] informalKISS if two people smooch, they kiss and hold each other in a romantic way, especially while dancing→ See Verb table
Examples from the Corpus
smooch• The sales manager and the boss's wife were smooching in full view of everyone.• In the semi-darkness, couples were smooching to sentimental love-songs.Origin smooch (1900-2000) smouch “to kiss” ((16-19 centuries)) 