1 : marked by calm self-control (especially in trying circumstances); unemotional; "play it cool"; "keep cool"; "stayed coolheaded in the crisis"; "the most nerveless winner in the history of the tournament"
2 : unhurried and relaxed; "a mellow conversation"
3 : not hurried or forced; "an easy walk around the block"; "at a leisurely (or easygoing) pace"
4 : in full control of your faculties; "the witness remained collected throughout the cross-examination"; "perfectly poised and sure of himself"; "more self-contained and more dependable than many of the early frontiersmen"; "strong and self-possessed in the face of trouble"
5 : free of trouble and worry and care; "the carefree joys of childhood"; "carefree millionaires, untroubled financially"
6 : (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"
