Bemused describes the look or feeling of someone who cannot quite work out what is happening. It is an adjective, and it does two jobs. It describes a person — "she looked bemused" — and it describes the things a face does: a bemused smile, a bemused expression, a bemused silence. Those noun pairings are where you will meet it most; the word lives on faces. The feeling it names is gentle. A bemused person is not frightened or angry; they are mildly puzzled, often with a half-smile, the way you look when someone tells a joke you don't get but you can see they meant well. This is a more common word than the verb bemuse — most learners will meet bemused first and may never meet bemuse at all. One honest note: because it sounds so close to amused, some speakers now use bemused to mean "quietly entertained." Careful writers dislike this, and dictionaries still give confusion as the meaning. Write it as confusion; just don't be surprised when you hear someone use it the other way.