  Features of Gas-Liquid (GL) and Quark-Hadron (QH) phase transitions (PT) in
dense nuclear matter are under discussion in comparison with their terrestrial
counterparts, e.g. so-called "plasma" PT in shock-compressed hydrogen,
nitrogen, xenon etc. Both, GLPT and QHPT, when being represented in widely
accepted $T - \mu$ diagram, are often considered as similar, i.e. amenable to
one-to-one mapping by simple scaling. It is argued that this impression is
illusive and that GLPT and QHPT belong to different classes: namely, GLPT is
typical \emph{enthalpic} (VdW-like) PT while QHPT ("deconfinement-driven") is
typical \emph{entropic} PT like hypothetical ionization- and
dissociation-driven phase transitions in hot and dense hydrogen, nitrogen etc.
of megabar pressure range. Newly introduced terms "enthalpic" and "entropic"
PT, are defined and clarified in their illustrative comparison successively
from $T - \mu$ to $P - T$ and $P - V$ phase diagrams for GLPT and QHPT from one
side (dense nuclear plasma) vs. GLPT and "plasma" (or "dissociative") PTs from
another side (electromagnetic plasma). Fundamental difference in topology of
binodal and spinodal curves for enthalpic and entropic phase transitions are
discussed and illustrated. Multilayered structure of thermodynamic surfaces
$T(P,V)$, $U(P,V)$, $S(P,V)$ etc. as basic origin for intrinsic anomalous
properties of all entropic PTs, is stressed.
