Give a note to the down-and-out (5)
I believe the answer is:
endow
'give' is the definition.
(I've seen this before)
'a note to the down-and-out' is the wordplay.
'a note' becomes 'do' (musical note, as in do-re-mi).
'to the down-and' becomes 'enw' (I am not sure about this - if you are sure you should believe this answer much more).
'out' means one lot of letters goes inside another.
'do' inserted inside 'enw' is 'ENDOW'.
Can you help me to learn more?
(Other definitions for endow that I've seen before include "Provide with a permanent income - perhaps a college" , "Establish (university post) by giving funds" , "Provide (with financial support, qualities etc)" , "Provide as a gift" , "Give permanent income to" .)