[1] : The Collaborative International Dictionary of English v.0.48

wilful \wil"ful\, a., wilfully \wil"fully\, adv., wilfulness
\wil"fulness\, n.
   see willful, willfully, and willfulness.
   1913 webster
see also:
willful willfully willfulness 

[2] : WordNet (r) 2.0

wilful
     adj 1: done by design; "the insult was intentional"; "willful
            disobedience" syn: intentional, willful
     2: habitually disposed to disobedience and opposition syn: froward,
         headstrong, self-willed, willful
     3: by conscious design or purpose; "intentional damage"; "a
        knowing attempt to defraud"; "a willful waste of time"
        syn: deliberate, intentional, knowing, willful
see also:
intentional willful froward headstrong self-willed deliberate 
knowing 

Wilful >> W Words
Wilful, definition of term: Wilful
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