Husband regularly penned ribaldry as rhetorical device (9)
I believe the answer is:
hendiadys
'rhetorical device' is the definition.
(hendiadys is a kind of rhetorical device)
'husband regularly penned ribaldry as' is the wordplay.
'husband' becomes 'h' (abbreviation).
'regularly' means one should take alternating letters (regularly take one letter, leave next etc.).
'penned'+'ribaldry'+'as'='pennedribaldryas'
The alternating letters of 'pennedribaldryas' are 'endiadys'.
'h'+'endiadys'='HENDIADYS'
(Another definition for hendiadys that I've seen is " Rhetorical device".)