serene
US /səˈriːn/
UK /səˈriːn/

1.
sereno, calmo, tranquillo
calm, peaceful, and untroubled; tranquil
:
•
The lake was serene in the early morning light.
Il lago era sereno nella luce del mattino presto.
•
She had a serene expression on her face.
Aveva un'espressione serena sul viso.