Chouette is an expression that you need to know in French! The noun chouette refers to an owl. However, the adjective chouette is used to express positive feelings towards someone or something and is an equivalent of “great”, “nice” or “pleasant”. J’ai passé une chouette soirée. I had a nice evening. Or Chouette! j’ai reçu mon colis! Great! I got my parcel! 

The origin of the expression is not well known. However, it might come from the verb “choeter” which used to mean “to be trendy”. A derivative from this verb is the adjective chou, cute. Chou? Chouette?