Old lady wearing corset, finding special staple (8)
I believe the answer is:
mainstay
'special staple' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'old lady wearing corset' is the wordplay.
'old lady' becomes 'ma' (both can mean mother).
'wearing' becomes 'in' (as in being 'in' certain clothes).
'corset' becomes 'stay' (I can't justify this - if you can you should give a lot more credence to this answer).
'ma'+'in'+'stay'='MAINSTAY'
'finding' is the link.
Can you help me to learn more?
(Other definitions for mainstay that I've seen before include "Chief support, like mast cable" , "Bulwark" , "Strong cable that secures a mast, chief support generally" , "Piece of rigging" , "chief supporter" .)