Source : Webster's Revised Unabridged Dictionary (1913)

Earnestness \Ear"nest*ness\, n.
   The state or quality of being earnest; intentness; anxiety.

         An honest earnestness in the young man's manner. --W.
                                                  Irving.

Source : WordNet®

earnestness
     n 1: an earnest and sincere feeling [syn: {seriousness}, {sincerity}]
     2: the trait of being serious; "a lack of solemnity is not
        necessarily a lack of seriousness"- Robert Rice [syn: {seriousness},
         {serious-mindedness}, {sincerity}] [ant: {frivolity}]