Synonyms of the word 
UNMALLEABLE → INTRACTABLE
unmalleable
- adj. Not malleable.
intractable
- adj. Not tractable; not able to be managed, controlled, governed or directed.
- adj. (mathematics) Not able to be solved (of a mathematical problem).
- adj. Stubborn; obstinate (of a person).
- adj. (medicine) Difficult to treat (of a medical condition).
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