Source : Webster's Revised Unabridged Dictionary (1913)

Properness \Prop"er*ness\, n.
   1. The quality of being proper.

   2. Tallness; comeliness. [Obs.] --Udall.

Source : WordNet®

properness
     n : correct or appropriate behavior [syn: {propriety}, {correctitude}]
         [ant: {impropriety}, {impropriety}]