The route to the interior (6)
I believe the answer is:
throat
This might be a double definition.
'the route' is the first definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'the interior' is the second definition.
Although both the answer and definition are singular nouns, I cannot understand how they can define each other.
'to' is the link.
Can you help me to learn more?
(Other definitions for throat that I've seen before include "Top part of the windpipe" , "Forepart of the neck" , "Where the gullet and windpipe are located" , "end of gaff" , "A frog is a problem in this" .)