depth

depth /ˈdɛpθ/ noun
plural depths
depth
/ˈdɛpθ/
noun
plural depths
Britannica Dictionary definition of DEPTH
1 
a  : a distance below a surface
[count]
[noncount]
b  [count] : the distance from the front of something to the back — usually singular
2 
[count] : an area that exists far below a surface or far inside something : a deep place or area — usually plural
— often used figuratively
3 
[count]
a  : a very low or bad state or condition — usually plural
b  : the worst part of something
4 
[noncount] : the quality of being deep: such as
a  : the quality of being strongly felt
b  : the quality of being very bad or serious
c  : the quality of being complete or thorough
d  : the quality of being strong in color, taste, etc.
e  : the quality of being low in sound
f  US, sports : the quality of having many good players on a team

in depth

: in a thorough or complete way
— see also in-depth

out of your depth

also beyond your depth
1 
: dealing with a situation or subject that is too difficult for you
2 
chiefly British : in water that is deeper than your height