Deliberate
late Middle English (as an adjective): from Latin deliberatus, ‘considered carefully’, past participle of deliberare, from de- ‘down’ + librare ‘weigh’ (from libra ‘scales’).
wiktionary
From Latin deliberatus, past participle of delibero(“I consider, weigh well”), from de + *libero, libro(“I weigh”), from *libera, libra(“a balance”); see librate.
etymonline
deliberate (adj.)
early 15c., "done with careful consideration," from Latin deliberatus "resolved upon, determined," past participle of deliberare "consider carefully, consult," literally "weigh well," from de, here probably "entirely" (see de-) + -liberare, altered (probably by influence of liberare "to free, liberate") from librare "to balance, make level," from libra "pair of scales, a balance" (see Libra). Meaning "characterized by slowness in decision, consciously unhurried" is attested by 1590s. Related: Deliberateness.
deliberate (v.)
1540s, "weigh in the mind, consider carefully;" 1550s, "discuss and examine the reasons for or against," from Latin deliberatus, past participle of deliberare "consider carefully, consult," literally "weigh well," from de, here probably "entirely" (see de-) + -liberare, altered (probably by influence of liberare "to free, liberate") from librare "to balance, make level," from libra "pair of scales, a balance" (see Libra). Related: Deliberated; deliberating. The earlier form of the verb in English was deliberen (late 14c.), from Old French deliberer and directly from Latin deliberare.