The Etymology of Deliberate
To deliberate is to weigh — and not metaphorically. Latin dēlīberāre was built from dē- ('thoroughly') and lībra ('a balance, a set of scales'), making its original sense entirely physical: to place arguments on the pans of a scale and see which side drops. The same lībra produced the zodiac sign Libra, the abbreviation 'lb' for pound, and the word 'equilibrium.' English borrowed the adjective form in the 15th century, initially in legal contexts where juries deliberated — still the most literal surviving use, as jurors weigh evidence. The verb sense ('to deliberate on a matter') and the adjective sense ('a deliberate act') entered simultaneously, though the adjective has developed a pronunciation split: /dɪˈlɪb.ər.ət/ for the adjective, /dɪˈlɪb.ər.eɪt/ for the verb.