Fast runners saving a thousand pounds for sultanas (6)
I believe the answer is:
harems
'fast runners saving a thousand pounds for sultanas' is the definition.
I can't tell whether this defines the answer.
'fast runners saving a thousand' is the wordplay.
'fast runners' becomes 'hares' (I've seen this in another clue).
'saving' means one lot of letters goes inside another.
'a thousand' becomes 'M' (Roman numeral for a thousand).
'hares' going around 'm' is 'HAREMS'.
Can you help me to learn more?
(Other definitions for harems that I've seen before include "Masher found in quarters of Muslim women" , "Wives' associations" , "quarters reserved for females" , "Seraglios, women's quarters in Muslim household" .)