Learner's definition of DEVILISH
[more devilish; most devilish]
2 : showing a desire to cause trouble but in a way that is not serious
She was attracted by his devilish charm.
There was a devilish look of mischief in her eyes.
a devilish [=mischievous] grin
have a devilish timeinformal + somewhat old-fashioned
: to have a difficult time doing something