Leading politician blocking most admired person for key spot on board? (7)
I believe the answer is:
topmast
'leading politician blocking most admired person for key' is the definition.
I can't tell whether this definition defines the answer.
'spot on board?' is the wordplay.
'spot' becomes 'top' (top is a kind of spot).
'on board?' becomes 'mast' (I can't justify this - if you can you should give a lot more credence to this answer).
'top'+'mast'='TOPMAST'
Can you help me to learn more?
(Other definitions for topmast that I've seen before include "high post" , "Part of square-rigged ship" , "High part of sailing ship" , "Most apt (anag) - feature of a square-rigged ship" , "Sail up here" .)