refractory
[adjective]
Synonyms: unmanageable, difficult, disobedient, headstrong, intractable, uncontrollable, unruly, wilful

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Antonyms: malleable

[TahlilGaran] English Synonym Dictionary ▲

re‧frac‧to‧ry /rɪˈfræktəri/ adjective
[Date: 1600-1700; Language: Latin; Origin: refractarius, from refragari 'to oppose']

1. formal deliberately not obeying someone in authority and being difficult to deal with or control Synonym : unruly

2. medical a refractory disease or illness is hard to treat or cure

[TahlilGaran] Dictionary of Contemporary English ▲