Help understanding Diamagnetism

I need some help understanding Wikipedia description of diamagnetism https://en.m.wikipedia.org/wiki/Diamagnetism

In the first sentence of the first paragraph, when said

"...induced magnetic field in the direction opposite the externally applied magnetic field, and are repelled by the magnetic field."

By direction opposite they are saying the direction of the magnetic field, or vector B in this depiction of the right hand rule? And, am i right in thinking that the directions of the fields being in opposition is why they repel each other?

Yes and yes. The directions of the magnetic field lines refer to the direction of $\vec{B}$. Since the external and induced magnetic field vectors face in opposite directions to each other, there is a repulsive force.