Irrational aerialists lose it over regular payments (8)
I believe the answer is:
salaries
'regular payments' is the definition.
(salary is a kind of regular payment)
'irrational aerialists lose it' is the wordplay.
'irrational' is an anagram indicator.
'lose' is a deletion indicator.
'aerialists' with 'it' taken out is 'aeraliss'.
'aeraliss' with letters rearranged gives 'SALARIES'.
'over' is the link.
(Other definitions for salaries that I've seen before include "Payments from employers" , "remuneration" , "Wages" .)