Synonyms of tranquil

1. placid, quiet, still, tranquil, smooth, unruffled, calm (vs. stormy): usage: (of a body of water) free from disturbance by heavy waves; "a ribbon of sand between the angry sea and the placid bay"; "the quiet waters of a lagoon"; "a lake of tranquil blue water reflecting a tranquil blue sky"; "a smooth channel crossing"; "scarcely a ripple on the still water"; "unruffled water"
2. calm, unagitated, serene, tranquil, composed (vs. discomposed): usage: 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"