from
The Collaborative International Dictionary of English v.0.48
Equilibrium \E`qui*lib"ri*um\, n.; pl. E. {Equilibriums}, L.
{Equilibria}. [L. aequilibrium, fr. aequilibris in
equilibrium, level; aequus equal + libra balance. See
{Equal}, and {Librate}.]
1. Equality of weight or force; an equipoise or a state of
rest produced by the mutual counteraction of two or more
forces.
[1913 Webster]
2. A level position; a just poise or balance in respect to an
object, so that it remains firm; equipoise; as, to
preserve the equilibrium of the body.
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Health consists in the equilibrium between those two
powers. --Arbuthnot.
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3. A balancing of the mind between motives or reasons, with
consequent indecision and doubt.
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{Equilibrium valve} (Steam Engine), a balanced valve. See
under {Valve}.
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