"crusial" is probably misspelled. Trying crucial instead Definition of crucial
1
[ adjective ] of extreme importance; vital to the resolution of a crisis

Synonyms

important

Examples

"a crucial moment in his career" "a crucial election" "a crucial issue for women"

2
[ adjective ] having crucial relevance

Synonyms

relevant

Examples

"crucial to the case" "relevant testimony"

3
[ adjective ] of the greatest importance

Examples

"the all-important subject of disarmament" "crucial information" "in chess cool nerves are of the essence"

4
[ adjective ] of the greatest importance

Examples

"the all-important subject of disarmament" "crucial information" "in chess cool nerves are of the essence"

5
[ adjective ] having the power or quality of deciding

Examples

"the crucial experiment" "cast the deciding vote" "the determinative (or determinant) battle"

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