Industrial engineer can tile outside of church (9)
I believe the answer is:
technical
'industrial' is the definition.
(thesaurus)
'engineer can tile outside of church' is the wordplay.
'engineer' indicates anagramming the letters.
'outside of' says to hollow out the word (remove centre letters).
'church' with its middle taken out is 'ch'.
'can'+'tile'+'ch'='cantilech'
'cantilech' is an anagram of 'TECHNICAL'.
(Other definitions for technical that I've seen before include "sort of college" , "- Drawing; - foul" , "as per strict rules" , "requires special skill" , "Requiring specialist knowledge" .)