#1 serene s. [calm, unagitated, tranquil] not agitated; without losing self-possession; "spoke in a calm voice"; "remained calm throughout the uproar"; "he remained serene in the midst of turbulence"; "a serene expression on her face"; "she became more tranquil"; "tranquil life in the country". wn
#2 serene s. completely clear and fine; "serene skies and a bright blue sea". wn
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