adj. 25B6; adjective
a wonderfully tranquil village : PEACEFUL, calm, restful, quiet, still, relaxing, undisturbed.
Martha smiled, perfectly tranquil : CALM, serene, relaxed, unruffled, unperturbed, unflustered, untroubled, composed, {cool, calm, and collected}; equable, even-tempered, placid, phlegmatic; informal unflappable.
busy, excitable.