Asleep, Ian often holds Joanna (5)
I believe the answer is:
piano
'joanna' is the definition.
(cockney rhyming slang for piano)
'asleep ian often holds' is the wordplay.
'holds' indicates a hidden word.
'PIANO' can be found hidden inside 'asleep ian often'.
(Other definitions for piano that I've seen before include "In music, soflty" , "Soft - musical instrument" , "Quiet (music)" , "Upright type?" , "p (mus.)" .)