Shrewd lot of wives put money first being considered mad (5,4)
I believe the answer is:
march hare
'considered mad' is the definition.
I can't judge whether this definition defines the answer.
'shrewd lot of wives put money first' is the wordplay.
'shrewd' becomes 'arch' (I've seen this before).
'lot of' means to remove the last letter (a lot of the word but not all of it).
'wives' becomes 'harem' (I've seen this before).
'put money' becomes 'm' (I can't justify this - if you can you should give a lot more credence to this answer).
'first' says to put letters next to each other.
'harem' with its last letter removed is 'hare'.
'arch'+'hare'='archhare'
'archhare' after 'm' is 'MARCH HARE'.
'being' acts as a link.
Can you help me to learn more?
(Other definitions for march hare that I've seen before include "Character at the tea-party in Alice's Adventures in Wonderland" , "seen at endless party" , "Animal in state of wild behaviour, starting with 3rd month?" , "Supposedly mad creature" , "character encountered by Alice" .)