Ordinal produced by philosopher in hot resort (9)
I believe the answer is:
millionth
'ordinal' is the definition.
(similar in meaning)
'philosopher in hot resort' is the wordplay.
'philosopher' becomes 'mill' (I've seen this before).
'resort' indicates anagramming the letters.
'in'+'hot'='inhot'
'inhot' with letters rearranged gives 'ionth'.
'mill'+'ionth'='MILLIONTH'
'produced by' acts as a link.
(Other definitions for millionth that I've seen before include "a very tiny bit?" , "ordinal" .)