Synonyms for Self-will (same or very similar meaning)
WordNet sense 1 (resolute adherence to your own ideas or desires):
bullheadedness, obstinacy, pigheadedness, stubbornness, obstinance
WordNet sense 2 (the trait of resolutely controlling your own behavior):
possession, self-command, self-control, self-possession, willpower
From the ODE community, based on WordNet
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