adjective

crucial

KROO-shul/ˈkruːʃl/

Extremely important in determining an outcome.

Checking the safety connection is crucial before the climber moves.

Climber checks central safety connection.

Etymology

The cross became an image of a signpost at a fork, where a choice must be made. From a test deciding between alternatives, crucial came to mean decisive for an outcome.

In context

Dr Nima | Eye33:11

the role that our Administration staff can play in having posters up and sign posting in that kind of way is so crucial to this catching this group of patients

NASS Axial SpA Uveitis Rheumatology Ophthalmology Nima Ghadiri Ankylosing Spondylitis HLA B27 Inflam

More examples

Early treatment plays a crucial role in recovery.
Your vote could be crucial to the election's outcome.
It is crucial that everyone follows the evacuation plan.

Forms

crucial

crucially adverb — In a way that decisively affects outcomes.

Similar words

critical: Often emphasizes urgency or danger at a turning point.
essential: Means necessary, not always directly determining the final outcome.
decisive: More directly stresses settling an issue or determining results.