SYN: Antagonist, foe, enemy, rival, assailant.
ANT: Accessory, abettor, alder, friend, helper, assistant, ally, accomplice.
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KEY: Adverse.
SYN: Opposed to, unlucky, hard, hostile, antagonistic, unpropitious, opposite, conflicting, contrary, unfavorable.
ANT: Favorable, friendly, amicable, propitious, fortunate, lucky.
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KEY: Adversity.
SYN: Ill-luck, misfortune, misery, calamity, disaster, distress, unsuccess, failure, ruin, trouble, affliction, sorrow.
ANT: Good-luck, prosperity, happiness, success, advancement.