Synonyms of the word 
SELF-POSSESSED → COLLECTED - COMPOSED - EQUANIMOUS - POISED - SELF-CONTAINED
self-possessed
- adj. in full control of one's faculties, and having a firm belief in one's abilities; confident, assured and…
collected
- adj. Cool‐headed, emotionally stable, in focus.
- v. simple past tense and past participle of collect.
composed
- adj. showing composure.
- v. simple past tense and past participle of compose.
equanimous
- adj. Calm and composed; of stable disposition.
poised
- adj. Possessing poise, having self-confidence.
- adj. Ready, prepared.
- v. simple past tense and past participle of poise.
self-contained
- adj. Not requiring external or additional support; complete in itself.
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