like clockwork Antonyms

accidentally aperiodically burdensomely challengingly demandingly discontinuously disorderedly disorganizedly distressfully effortfully episodically erratically spasmodically at one time or another from time to time haphazardly at random arduously changeably chaotically difficultly inconstantly infrequently interruptedly irregularly laboredly sporadically sweatily toughly assiduously not without difficulty