periodically Antonyms

on a daily basis every day day by day day after day most of the time at every turn at a stretch at all times as a whole night and day 24-7 as a rule every once in a while every so often from day to day at all hours of the day and night at one stretch on the odd occasion as a general rule hardly ever twenty-four seven seasonally repetitively on and on morning, noon and night in fits and starts habitually by fits and starts now and then oftentimes often occasionally incessantly generally frequently forever continuously continually constantly consistently permanently perpetually persistently from time to time at times at large day in and day out all the time all along again and again