However, I don't entirely grasp the physical meaning of conservative fields, I thought understanding where the label came from might help me understand what it is that we're describing.
It may be helpful to think in terms of the the conservative forces associated with conservative fields, like the gravitational and electromagnetic forces. A conservative force has the property that the total work done by the force in moving a particle between two points is independent of the path taken between the points. For example, the work done in moving a mass between two points in the gravitational field does depend not on the path taken.
The term "conservative" refers to the fact that the overall mechanical energy (kinetic + potential) of a particle is conserved. An example where mechanical energy is not the conserved is when kinetic friction forces are involved.
Hope this helps.