The Collaborative International Dictionary of English v.0.48:
Praiseworthiness \Praise"wor`thi*ness\, n. The quality or state of being praiseworthy. [1913 Webster]WordNet (r) 3.0 (2006):
praiseworthiness n 1: the quality of being worthy of praise [syn: praiseworthiness, laudability, laudableness]