On a basic level, yes, it does mean "smiling", that being the adjective, not the verb (e.g. A smiling man). However, it has the weight of "فعال" which indicates exaggeration, extremity, etc. Thus, Bassam means someone who smiles a lot. "Basim" on the other hand is basic, meaning "smiling" or "smiler".Fun fact, "Bassam" is the dubbed name of Hyuuga Kojiro of the Captain Tsubasa series.
Fun fact, "Bassam" is the dubbed name of Hyuuga Kojiro of the Captain Tsubasa series.