(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"
steadfast in affection or allegiance; "years of faithful service"; "faithful employees"; "we do not doubt that England has a faithful patriot in the Lord Chancellor"
not having sexual relations with anyone except your husband or wife, or your boyfriend or girlfriend; "he remained faithful to his wife"