From The Collaborative International Dictionary of English v.0.48 [gcide]:
Rosiness \Ros"i*ness\, n.
The quality of being rosy.
[1913 Webster]
From WordNet (r) 3.0 (2006) [wn]:
rosiness
n 1: a rosy color (especially in the cheeks) taken as a sign of
good health [syn: bloom, blush, flush, rosiness]
2: a healthy reddish complexion [syn: ruddiness, rosiness]
3: a dusty pink color [syn: rose, rosiness]