gucnuti

1. colloq. to take a sip; to take a swig
   Gucni malo, videćeš kako je dobro. — Take a sip, you'll see how good it is.
   Gucnuo je pivo i nastavio da priča. — He took a swig of beer and went on talking.
2. colloq. (of alcohol) to have a drink; to have a few
   Vidi se da je malo gucnuo na slavi. — You can tell he had a few at the slava.

Usually used with an accusative object or without one: gucnuti pivo, gucnuti malo.