Rick’s rant is out of order (6)
I believe the answer is:
strain
'rick's' is the definition.
(both can mean a physical pain)
'rant is out of order' is the wordplay.
'out of order' is an anagram indicator.
'rant'+'is'='rantis'
'rantis' with letters rearranged gives 'STRAIN'.
(Other definitions for strain that I've seen before include "Wrench; melody" , "line of ancestry" , "particular style of writing" , "'Stress, tension (6)'" , "Family - stress - air - force" .)