Challenging

Verb

1. Present participle of challenge

Full definition of challenging

Adjective

1. Difficult, hard to do.

Antonyms

• unchallenging

Noun

1. The act of making a challenge.
• Estcourt Rowland Metzner, The conflict of tax laws (page 151)There are always sincere challengings of the findings, always the objections (sincere in another sense) of those whose interests seem threatened.