Visual acuity refers to the sharpness of vision, specifically the ability to distinguish fine detail. It's often measured using a Snellen eye chart, where the smallest line you can read at a certain distance determines your visual acuity.

However, "distance at which an object or light can be clearly seen" might also be referring to:

* Visibility: This encompasses the general ability to see objects, influenced by factors like lighting, weather, and the object's contrast against the background.

* Detection distance: This refers to the maximum distance at which an object can be detected, even if not clearly seen. This is often used in contexts like radar or search and rescue operations.

To be more specific, could you provide more context about what you're looking for? For instance, are you talking about a specific object or light source? Are you referring to a medical context or a general one?