Definition of deep-sunk:
(adj) :
(of distance or position; also figurative) Extending, reaching or positioned far from a point of reference, especially downwards.
(adj) :
Extending far down from the top, or surface, to the bottom, literally or figuratively.
(adj) :
Positioned far from the surface or other reference point, especially down through something or into something.
(adj) :
Far in extent in another (non-downwards, but generally also non-upwards) direction, especially front-to-back.
(adj) :
(in combination) Extending to a level or length equivalent to the stated thing.
(adj) :
In a (specified) number of rows or layers.