crucial Synonyms

important essential all important rememberable required requisite resultful retiform right-hand salient seminal serious significant strategic needful relevant obligatory overriding palmiped paramount pivotal portentous preeminent prerequisite pressing prime primary principal prominent substantial substantive underlying life-and-death life-or-death lifesaving heavy-duty meaningful nonintersecting in particular straight-laced supercritical symbiotic top-grade world-shaking crit evaluative climactic upstream urgent valuable