Cutting a rectangular hollow into lumber -- what is the correct term?

Question

Any tips on how to do what I'm asking are welcome, but first of all I would like to ask for the correct terminology (because not knowing it prevents me from even Googling myself).

Maybe the title is not totally clear (because I don't know the right term), so let me explain in detail:

• suppose you have a thicker plank or other dimension lumber, something like this

• now let's say, you want to make the middle part more deep in a rectangular area, but not cut completely through the lumber, like this:

              +---------------------+
              |                     <------ untouched part
              | +-----------------+ |
              | |                 | |
              | |               <---------- deeper, flat, but not   
              | |                 | |       cut through surface
              | |                 | |
              | |                 | |
              | |                 | |
              | |                 | |
              | |                 | |
              | |                 | |
              | |                 | |
              | |                 | |
              | |                 | |
              | +-----------------+ |
              |                     |
              +---------------------+

One example use case, just to give an idea, would be building a table top from which the tools (like screw drivers, pencils, etc.) cannot roll down. (The actual use case I'm planning to do, is building a base for a power-strip, inspired by this answer.)

Questions

• What is this process called? (I thought I remembered something like "embeveling", but that is not the correct word, because it means "chopping off the edge at a degree.) -- This is actually the most important.

• What tools can be used to do this?

• What is the procedure for doing this?

Answer 1

Some of the words that fit your objective are mortise and recess. Typically a mortise is an opening cut part way into wood to receive a tenon to create a strong joint. A mortise is described also as a recess. You can also use inlay to find other useful references.

For a large area project as you describe, a set of chisels and gouges would be useful if you intend to perform this action using hand tools.

A method using power tools requires either a router table or a router jig. One could attempt the process without either, but the depth of the recess would be inconsistent and may not result in an acceptable appearance.

A more comprehensive answer can be found on this SE.