split second(n = noun.time) blink of an eye, flash, heartbeat, instant, jiffy, new york minute, trice, twinkling, wink - a very short time (as the time it takes the eye to blink or the heart to beat); "if I had the chance I'd do it in a flash"
is a kind of bit, minute, mo, moment, second

banana split, bits per second, cycle per second, gigacycle per second, kepler's second law, kilocycle per second, leap second, lickety split, light second, megacycle per second, million floating point operations per second, million instructions per second, newton's second law, newton's second law of motion, parallax second, reverse split, reverse stock split, second, second advent, second adventism, second adventist, second balcony, second banana, second base, second baseman, second battle of ypres, second best, second childhood, second class, second coming, second coming of christ, second council of constantinople, second council of lyons, second council of nicaea, second cousin, second cranial nerve, second crusade, second deck, second earl grey, second earl of chatham, second earl of guilford, second empire, second epistel of john, second epistle of paul the apostle to the corinthi, second epistle of paul the apostle to the thessalo, second epistle of paul the apostle to timothy, second epistle of peter, second epistle to the corinthians, second epistle to the thessalonians, second epistle to timothy, second estate, second fiddle, second gear, second growth, second half, second hand, second joint, second lateran council, second law of motion, second law of thermodynamics, second lieutenant, second marquis of rockingham, second moment, second mortgage, second nature, second period, second person, second power, second rate, second reading, second reich, second sacker, second sight, second stomach, second string, second thought, second thoughts, second to none, second trimester, second vatican council, second wind, second world war, split, split decision, split down, split dynamometer, split end, split hairs, split infinitive, split key, split level, split personality, split rail, split run, split shift, split shot, split stitch, split stroke, split stuff, split switch, split the difference, split ticket, split up, split wheel, stock split, trillion floating point operations per second, united society of believers in christ's second app, watt second