A specific area in the retina of vertebrate eyes where the optic nerve exits the eye, resulting in a lack of sensitivity to light and creating a region where visual perception is absent.

An aspect or detail that is often overlooked, even by those who are being cautious or thorough, leading to potential consequences or challenges.

An inconvenient or problematic element that goes unnoticed due to a lack of awareness or insight, often resulting in unexpected issues.

A metaphorical reference to gaps in knowledge or understanding, where critical information is missed despite efforts to be attentive or informed.