What is the word for "the space left when a shape is removed from something", like for example, the gingerbread-man shape left in the dough after the gingerbread-man has been cut out of it? Its not the "counterfoil", or "the negative"....I seem to remember there being a specific word for it, what is it?
It's simply a cutout.
Definition of cutout:
1: something cut out or off from something else; also: the space or hole left after cutting
Disambiguation may well be necessary.
If a shape is cut out, then what is left is a shaped space. The further description of the space depends on what was cut out :
A Mango Shaped Space
Durrington Walls - an oval shaped space
Car shaped space
the three body cavities - a horseshoe shaped space
Note : Due to the relative obscurity of the wording, some of these references are buried in the links I have provided. I guarantee that they are there, but they require a little searching to pinpoint them.
I think you may use outline:
the main shape or edge of something, without any details.
According to OLD, Imprint is:
A mark or outline made by pressing something on to a softer substance.
Example sentence (from the same link):
‘he made imprints of the keys in bars of soap’
In case of imprint, you should think of it like a stamp. If your gingerbread man uses some pattern that it imprints in the dough, this is the word your looking for. A similar example is a waffle iron, it presses a certain pattern on the food, that pattern may be called an imprint.
Form (noun) The visible shape or configuration of something.
- Nelly cut out her gingerbread man from the dough, leaving a form shaped exactly like her cookie (which she thought was hilarious).
While it might not be the specific word you are looking for, I liked Laurel's answer but it was only in the comments. I also liked Nigel's answer. For the widest understanding I would use "a gingerbread-man shaped hole was left behind in the dough"
Although I fear you want a single word, I would use cavity:
Definition of cavity plural cavities 1 : an unfilled space within a mass; especially : a hollowed-out space
The gingerbread-man cavity
How about Trace.
a mark, object, or other indication of the existence or passing of something.
Source: Google Dictionary