Other forms: worrisomely
If something is worrisome, it bothers or upsets you. Your nervous dog may find the sound of thunder extremely worrisome.
When the news reports are full of worrisome developments — crime, climate change, local budget cuts — it can be reassuring to hear some good news, which is why many news broadcasts also include feel-good stories about lost pets reunited with their owners and kids raising money for the local library. Worrisome things do just what you'd think: they make you worry. This word first appeared around 1820 in North America, and it's been used ever since for things that cause distress.