What is the definition or description of: lazy eye?

See Below: A "lazy eye" is a generic term that is often used to describe when one eye (1) does not see as well as another eye or (2) does not align properly with the other eye.

Amblyopia: Lazy eye is the layman's term for amblyopia or strabismus. One of the eyes is truly weaker and usually deviates in (toward the nose) or out (toward the ear)...And hence is "lazy.".