Meaning of "deep" in Essential American English Dictionary

deep

adjective us /dip/

A2 having a long distance from the top to the bottom or from the front to the back:

The water is a lot deeper than it seems.

B1 A deep color is strong and dark:

deep brown eyes
one metre, six feet, etc. deep

one metre, six feet, etc. from the top to the bottom, or from the front to the back:

This end of the pool is two metres deep.
one inch, six feet, etc. deep

one inch, six feet, etc. from the top to the bottom, or from the front the back:

This end of the pool is eight feet deep.

A deep feeling is very strong:

a deep sleep

the action of someone sleeping in a way that makes it difficult to wake them up

A deep sound is low:

a deep voice

(Definition of “deep adjective” from the Webster's Essential Mini Dictionary © Cambridge University Press)