← BackshareGuessplacidness/ˈplæsɪdnəs/nounThe quality or state of being calm, peaceful, and undisturbed.The placidness of the garden helped her relax after a long day.His placidness during the argument surprised everyone.The placidness of the sea made for a perfect sailing trip.SynonymsserenitycalmnesspeaceAntonymsagitation