Unprotected means not shielded or defended from danger, harm, or difficult conditions. When something is unprotected, it's vulnerable to whatever might threaten or damage it.

If you leave your bicycle outside unprotected during a rainstorm, it has nothing covering it or keeping the rain away. An unprotected plant left in freezing weather has no greenhouse or covering to shield it from the cold. In sports, an unprotected goal has no goalie defending it, making it easy for opponents to score.

The word also describes people or things lacking safety measures. A computer without security software is unprotected from viruses. A hiker without sunscreen has unprotected skin that might burn. Workers need helmets and gloves to avoid having unprotected heads and hands in dangerous jobs.

Being unprotected isn't always terrible: sometimes we choose to go unprotected when the risk seems small. You might walk outside without an umbrella on a cloudy day, leaving yourself unprotected from possible rain. But when real dangers exist, like crossing a busy street or handling sharp tools, being unprotected means taking unnecessary risks. The opposite is protected, meaning guarded, shielded, or kept safe from harm.