As a Noun:
1. The quality of being important, necessary or significant in a particular situation. English = importance.
As a Verb or Adjective:
1. To be very significant, valuable, or necessary. English = (be) important.
2. Of something, to be more important or better than other things of its kind. English = (be) special, (be) exceptional, (be) outstanding.
1. Used in a phrase to indicate that what you are saying applies more to one thing or situation than to any other. English = especially.