puckishly
Concise Oxford English Dictionary © 2008 Oxford University Press:
puckish/ˈpʌkɪʃ/
▶adjective playful, especially in a mischievous way.
– derivatives
puckishly adverb,
puckishness noun.
puckishly adverb,
puckishness noun.
'puckishly' also found in these Oxford entries:

