Penny in Angola, the new 50p is like this (10)
I believe the answer is:
heptagonal
'50p is like this' is the definition.
The definition suggests a singular noun but the answer is not.
'penny in angola the new' is the wordplay.
'penny' becomes 'p' (short for pence).
'in' means one lot of letters goes inside another.
'new' indicates anagramming the letters.
'angola'+'the'='angolathe'
'angolathe' is an anagram of 'hetagonal'.
'p' going inside 'hetagonal' is 'HEPTAGONAL'.
Can you help me to learn more?
(Another definition for heptagonal that I've seen is " Seven-sided".)