Steady state theory, a non-standard cosmological view developed in 1949 by Fred Hoyle and others as an alternative to the Big Bang theory

Steady state (chemistry), a central term in chemical kinetics

Steady state (macroeconomics), where a time series variable reaches when its growth rate in time remains constant

Steady state (electronics), a state existing in a circuit or network when all transients have died away

Steady state engine test stand, a type of application for engine testing

Steady state (biochemistry), a central term in osmosis