Brown recluse, also known as violin spiders, is a venomous species of spider found mainly in the United States. These spiders are typically light to dark brown in color with a characteristic violin-shaped marking on their head. While they are not aggressive, their venom can cause serious health problems, including necrosis or tissue death. Due to their potent venom, many people are scared of brown recluse spiders, and for good reason. Synonyms for brown recluse include fiddleback spider, Loxosceles reclusa, violin spider, and brown spider. Regardless of what you call them, it's best to avoid these dangerous arachnids and seek medical attention if bitten.