Crossword Genius

Mad keen about making toys, here's a connective part (8)

Ross

I believe the answer is:

keystone

I'm a little stuck... Click here to teach me more about this clue!

'a connective part' is the 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?

'mad keen about making toys' is the wordplay.
'mad' indicates an anagram.
'about' indicates putting letters inside.
'making' is an anagram indicator.
'keen' with letters rearranged gives 'kene'.
'toys' with letters rearranged gives 'ysto'.
'kene' enclosing 'ysto' is 'KEYSTONE'.

'here's' acts as a link.

Can you help me to learn more?

(Other definitions for keystone that I've seen before include "Piece at the top of a masonry arch" , "Central part of a system" , "Important piece at apex of arch" , "Something on which all else depends" , "Central part of arch" .)

I've seen this clue in the Evening Standard.
Want a hint initially instead of a full solution? Install my app