challenge Synonyms - page 2

go against debunk koan take the bull by the horns disagree with becall major challenge difficult task object to square off showdown shootout recusal recalcitrancy Gordian knot face-off blow out of the water war vie undercut ultimatum trouble tournament tickler test waylay whereto withsay jigsaw destabilize assert oneself ask for trouble ask for take on call out wrestle tackle object difficulty counter controvert contraversion contraposition contradict contestation contest contend counterwork cross-examine cut-off