To expose something means to uncover it or make it visible, whether literally or figuratively. When you expose film to light in an old camera, you're letting light hit it so it can capture an image. When construction workers expose underground pipes while digging, they reveal something that was hidden beneath the soil.

The word often describes revealing something that someone wanted to keep secret. A journalist might expose corruption in government by publishing documents that prove wrongdoing. In these cases, exposing means bringing truth to light, making the hidden visible so people can see what's really happening.

Expose can also mean putting something at risk or in a vulnerable position. When you expose yourself to cold weather without a jacket, you're leaving yourself unprotected. A general might worry about exposing troops to enemy fire. Scientists talk about exposure to germs or chemicals, meaning contact that could cause harm.