blind spot

Concise Oxford English Dictionary © 2008 Oxford University Press:
blind spot

▶noun

• 1 Anatomy the point of entry of the optic nerve on the retina, insensitive to light.

• 2 an area where a person's view is obstructed.

  ■ an area in which a person lacks understanding or impartiality.

• 3 Telecommunications a point within the normal range of a transmitter where there is unusually weak reception.