CHALLENGE Synonyms: 175 Similar and Opposite Words - Merriam-Webster
https://www.merriam-webster.com/thesaurus/challenge
WEBSynonyms for CHALLENGE: objection, exception, question, complaint, protest, difficulty, criticism, fuss; Antonyms of CHALLENGE: willingness, approval, sanction, agreement, acceptance, compliance, obedience, acquiescence
DA: 64 PA: 65 MOZ Rank: 65