crucial

adjectives

of extreme importance; vital to the resolution of a crisis
"a crucial moment in his career"; "a crucial election"; "a crucial issue for women"
crucial, important
is derived from
cruciality
antonym
noncrucial
having crucial relevance
"crucial to the case"; "relevant testimony"
crucial
is similar to
directly relevant to a matter especially a law case
"his support made a material difference"; "evidence material to the issue at hand"; "facts likely to influence the judgment are called material facts"; "a material witness"
material
of the greatest importance
"the all-important subject of disarmament"; "crucial information"; "in chess cool nerves are of the essence"
all important, all-important, crucial, essential, of the essence
is derived from
cruciality