Webster's Revised Unabridged Dictionary · 1913

Librate

Librate (lī"brāt) , intransitive verb

[Latin libratus, past participle of librare to balance, to make even, from libra. Compare Level, Deliberate, Equilibrium.]

To vibrate as a balance does before resting in equilibrium; hence, to be poised.
Their parts all librate on too nice a beam. — Clifton

Librate , transitive verb

To poise; to balance.