Attend to mysterious runes (5)
I believe the answer is:
nurse
'attend to' is the definition.
(thesaurus)
'mysterious runes' is the wordplay.
'mysterious' indicates an anagram.
'runes' anagrammed gives 'NURSE'.
(Other definitions for nurse that I've seen before include "One caring for patient" , "Care for - harbour" , "Patient tender" , "Hospital employee" , "Who cares" .)