Penny was on top, holding one in bed tight (9)
I believe the answer is:
plastered
'tight' is the definition.
(synonyms)
'penny was on top holding one in bed' is the wordplay.
'penny' becomes 'p' (short for pence).
'was on top' becomes 'led' (I've seen this in another clue).
'holding' indicates putting letters inside.
'one in bed' becomes 'aster' (I am not sure about this - if you are sure you should believe this answer much more).
'led' going around 'aster' is 'lastered'.
'p'+'lastered'='PLASTERED'
Can you help me to learn more?
(Other definitions for plastered that I've seen before include "Like member in cast" , "the worse for drink" , "Intoxicated" , "incapable" , "wasted" .)