Personally, I favor the term “cooling tower,” because that’s what it is and does. (Chimney works for me, too – if a chimney is something that moves air from the ground to a higher altitude by virtue of the “chimney effect”, i.e., hot air rises.) I do recall studying (back in grad school) large-scale cooling towers that were entirely natural-convection driven – probably in the context of fission-based power generation. I don’t see why that existing technology wouldn’t be directly adaptable to any power plant, FF in particular.