Li·brate v. i. [imp. & p. p. Librated p. pr. & vb. n. Librating.] To vibrate as a balance does before resting in equilibrium; hence, to be poised.
Their parts all librate on too nice a beam. --Clifton.
Li·brate, v. t. To poise; to balance.
v 1: determine the weight of; "The butcher weighed the chicken"
2: vibrate before coming to a total rest; "the children's swing