In wikipedia page about hadrons the following image appears:
I can understand why the intersection between hadrons and fermions are baryons, as a way to say a baryon is a kind of hadron composed of several quark fermions.
However, what is the meaning of the intersection between hadron and bosons labeled in the picture as mesons? If I understand correctly, a meson consists of one quark and one antiquark, nothing related to any boson.