(cryogenics) the lowest temperature theoretically attainable (at which the kinetic energy of atoms and molecules is minimal); 0 Kelvin or -273.15 centigrade or -459.67 Fahrenheit
quick and energetic; "a brisk walk in the park"; "a lively gait"; "a merry chase"; "traveling at a rattling rate"; "a snappy pace"; "a spanking breeze"
not sympathetic or disposed toward; "unsympathetic officialdom"; "people unsympathetic to the revolution"; "his dignity made him seem aloof and unsympathetic"
(of characters in literature or drama) tending to evoke antipathetic feelings; "all the characters were peculiarly unsympathetic"