1. serene
Today's serene sky makes me very optimistic.
Her face was serene.
"he remained serene in the midst of turbulence"; "a serene expression
He apologizes to Mike, who is sitting there like a serene Buddha.
I think that such a serene person cannot be dangerous.
It was important to her that her environment be calm and serene, free from drama and chaos.
Your daughter is so serene!
She has a lovely serene face.
I feel mermaid - beautiful and serene
The autumn sky is clear and serene.
The view of Mars through earthly telescopes suggested that all was serene.
2. very calm
3. as cool as cucumber