Extremely plaintive, desperate appeal for money abroad (5)
I believe the answer is:
pesos
'money abroad' is the definition.
I can't tell whether this definition defines the answer.
'extremely plaintive desperate appeal' is the wordplay.
'extremely' suggests removing the centre (only the extremes of the word are used).
'desperate appeal' becomes 'sos' (I have seen 'urgent appeal' mean 'sos' so perhaps 'appeal' could also mean 'sos'. I am not sure about the 'desperate' bit.).
'plaintive' with its middle taken out is 'pe'.
'pe'+'sos'='PESOS'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for pesos that I've seen before include "Mexican monetary units" , "Poses for Mexican money" , "Mexican dollars" , "Poses for Mexican coins" .)