established practice; custom
permanent; perpetual; lasting
constant; invariable; chronic; everlasting
homeostasis; homoeostasis; constancy
fixed property; real property; fixed occupation
starship; interstellar spacecraft
10^52 (or 10^56); innumerable
a constant (e.g. in science)
identity mapping; identity function
star catalog; star catalogue
permanent establishment (in tax law)
permanent establishment (in tax law)
sphere of fixed stars (in the Ptolemaic system)
permanent income hypothesis
quasar; quasi-stellar object; QSO
starship; interstellar spacecraft
identity function; identity operator
perennial river; perennial stream; permanent river