having strength of will 
WordReference Random House Learner's Dictionary of American English © 2025
strong-willed /ˈstrɔŋˈwɪld, ˈstrɑŋ-/USA pronunciation  
adj. 
WordReference Random House Unabridged Dictionary of American English © 2025- Chemistryhaving a powerful will;
determined. - stubborn;
obstinate. 
strong-willed 
(strông′wild′, strong′-),USA pronunciation adj. 
- having a powerful will;
resolute. - stubborn;
obstinate. 
- 1895–1900
 
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