(a)quietcharacterized by an absence or near absence of agitation or activity“a quiet life”, “a quiet throng of onlookers”, “quiet peace-loving people”, “the factions remained quiet for almost 10 years”
(s)placid, quiet, still, tranquil, smooth, unruffled(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”
(r)quietly, quietwith little or no activity or no agitation (`quiet' is a nonstandard variant for `quietly')“her hands rested quietly in her lap”, “the rock star was quietly led out the back door”, “sit here as quiet as you can”