Could anyone tell me about lazy eyes?

May affect vision: Lazy eye generally refers to an uncorrectable or partially correctable suboptimal vision in one or both eyes for any variety of reasons. Commonly, a crossed-eye and/or a large amount of prescription in one eye can cause it to be "lazy" where the connections to the brain are underdeveloped, usually completed by age 10-12 years old.

In a nutshell: it means that the brain has not developed the visual system in an eye. This is usually the result of untreated refractive error (prescription for glasses) in early childhood or a crossed eye, but there are other reasons as well. After about the age of 6-8, there is no treatment for it. Prior to that age, patching of the better eye can help.