Computer device rejected in some domiciles (5)
I believe the answer is:
modem
'computer device' is the definition.
(I've seen this before)
'rejected in some domiciles' is the wordplay.
'rejected' says the letters should be written backwards.
'in' indicates the answer is hidden within the clue.
'medom' can be found hidden inside 'some domiciles'.
'medom' written backwards gives 'MODEM'.
(Other definitions for modem that I've seen before include "Computer communication device" , "electronic device" , "Unit connecting computer to phone line" , "Connector for computer to telephone line" , "Computer interface" .)