casually Antonyms

at once in an instant in no time accidentally on purpose all of the sudden anticipatorily antsily asudden at a stroke at full stretch in one fell swoop before you can say Jack Robinson as a rule neurotically like hell zealously vigorously by design assiduously all at once all of a sudden exclusively avidly seriously essentially laboriously quick as a flash excitedly undesirably voraciously worriedly in a trice like greased lightning in less than no time as fast as greased lightning in no time at all all at one time all in one go in a tick tetchily studiously strenuously fervently in a jiffy in one stroke lightning fast on a dime purposefully restively ruinously