/ ˈtʃælɪndʒɪŋ; NAmE / adjective
1.
difficult in an interesting way that tests your ability :
challenging work / questions / problems
a challenging and rewarding career as a teacher
➡ note at difficult
2.
done in a way that invites people to disagree or argue with you, or shows that you disagree with them :
She gave him a challenging look. 'Are you really sure?' she demanded.