American EnglishAmE informalWORRIED someone who worries a lot about unimportant things 〔为琐事〕自寻烦恼的人
Examples from the Corpus
worrywart• Would he have figured that I was just being a worrywart?• Don't be such a worrywart!• The cast also included NormanFell as the worrywartproducer.