If they tell you sei un fannullone (pronounced fahn-nool-loh-neh) you should either reconsider the people you hang with or your work ethics. While fannullone may sound pretty funny, with all those double consonants and the -one ending — doesn’t it make you think of something cuddly?— its meaning is not that pleasant, especially when they use the word to talk about you.
In Italian, a fannullone is someone who, quite simply, doesn’t like to work, nor engage in any type of activity involving reflection or effort: a slacker, we would say in English. The word is a relatively recent addition to the Italian dictionary, as it became popular around the mid-19th century. It comes from two other terms, the verb fare (to do) and the adverb nulla (nothing): so, literally, fannullone is someone who does nothing.