A subject or area about which one is uninformed or misinformed, often because of a prejudice or lack of appreciation.
A location where radio reception and/or transmission is significantly poorer than in surrounding locations.
A location around an earthquake epicentre that is prone to earthquake.
An inability to recognize a fact or think clearly about a certain topic, especially because of a prejudice.
The place where the optic nerve attaches to the retina, and so where the retina cannot detect light.
The part of the railway/tramway track that cannot be seen in the side mirror or the side window.
In driving, the part of the road that cannot be seen in the rear-view mirror.
In a stadium or auditorium, any location affording those seated or standing there only an obstructed visual or auditory experience.
Any thing, place, or situation about which nothing is known; an unknown fact or piece of information.
A variable (usually x, y or z) whose value is to be found.
A person of no identity; a nonentity
Not known; unidentified; not well known.