Yes, cent is surprisingly an indispensable thing (9)
I believe the answer is:
necessity
'thing' is the definition.
(I know that necessity is a type of thing)
'yes cent is surprisingly' is the wordplay.
'surprisingly' is an anagram indicator (a surprising ordering of the letters).
'yes'+'cent'+'is'='yescentis'
'yescentis' anagrammed gives 'NECESSITY'.
'an indispensable' acts as a link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for necessity that I've seen before include "Great need" , "Fundamental" , "Prerequisite - poverty" , "It's said to be the mother of invention" , "Need, exigency" .)