vital

This word means "necessary for existence," "essential," "indispensable." Vital is both overused and misused because in few applications is it used to mean what it really means. It is absurd to say "Helen's presence at the dance is vital" unless it is undeniable that Helen's absence will cause the dance to be an unqualified failure. Generally related words with less exaggerated meanings than vital include needed, wanted, beneficial, helpful, advantageous, desirable, useful, salutary, and serviceable, and in the sense of "important," effective, substantial, weighty, momentous, consequential, considerable, eminent, prominent, conspicuous, and significant.