equilibrium
n.
c.1600, "state of mental balance," from Latin aequilibrium "an even balance; a horizontal position," from aequilibris "equal, level, horizontal, evenly balanced," from aequus "equal" (see equal, adj.) + libra "a balance, scale, plummet" (see Libra). Related: Equilibrious.
〔李〕[equi=even相等的；libr=balance天平；-ium=the state表状态→] n. state of even balance平衡状态