Governor's frailty, getting broody regularly (7)
I believe the answer is:
viceroy
'governor's' is the definition.
(I've seen this before)
'frailty getting broody regularly' is the wordplay.
'frailty' becomes 'vice' ('vice' can be a synonym of 'frailty').
'getting' says to put letters next to each other.
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
The alternate letters of 'broody' are 'roy'.
'vice'+'roy'='VICEROY'
(Other definitions for viceroy that I've seen before include "Ruler of a colony" , "Monarch's plenipotentiary - American butterfly, like (but smaller than) a monarch" , "Governor ruling in name of sovereign" , "One ruling in a colony" , "sovereign's governor" .)