Synonyms for Composed (same or very similar meaning)
WordNet sense 1 (made or joined or united into one):
combined
WordNet sense 2 (marked by calm self-control (especially in trying circumstances); unemotional):
cool
WordNet sense 3 (in full control of your faculties):
collected, self-possessed
WordNet sense 4 (not agitated; without losing self-possession):
calm, serene, tranquil
From the ODE community, based on WordNet
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