Synonyms of the word 
UNFLUSTERED → COMPOSED - UNPERTURBED - UNRUFFLED
unflustered
- adj. Not flustered; calm.
composed
- adj. showing composure.
- v. simple past tense and past participle of compose.
unperturbed
- adj. Not perturbed.
unruffled
- adj. Calm, not ruffled, serene, at peace, unbothered.
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