'Gainfulness' definitions:

Definition of 'gainfulness'

From: WordNet
noun
The quality of affording gain or benefit or profit [syn: profitableness, profitability, gainfulness, lucrativeness] [ant: unprofitability, unprofitableness]

Definition of 'Gainfulness'

From: GCIDE
  • Gainful \Gain"ful\, a. Profitable; advantageous; lucrative. "A gainful speculation." --Macaulay. -- {Gain"ful*ly}, adv. -- {Gain"ful*ness}, n. [1913 Webster]