Folded card husband lost in TV fundraiser turned up (7)
I believe the answer is:
notelet
'folded card' is the definition.
(a folded card or paper for writing a note on)
'husband lost in tv fundraiser turned up' is the wordplay.
'husband' becomes 'h'.
'lost in' indicates named letters should be taken away.
'tv fundraiser' becomes 'telethon' (televised fundraiser).
'turned up' says the letters should be written in reverse.
'telethon' with 'h' taken out is 'teleton'.
'teleton' back-to-front is 'NOTELET'.
(Other definitions for notelet that I've seen before include "Paper folded" , "Folded sheet for an informal letter" , "Message card" , "Decorative letter" , "brief message" .)