Number of suits in outhouse not originally stored away (5)

'stored away' is the definition.
(I've seen this in another clue)

'number of suits in outhouse not originally' is the wordplay.
'number of suits' becomes 'IV' (Roman numerals - there are four playing card suits).
'in' means one lot of letters goes inside another.
'outhouse' becomes 'shed' (I've seen this before).
'not originally' means to remove the first letter (the origin of the word is removed).
'shed' with its first letter taken off is 'hed'.
'iv' put inside 'hed' is 'HIVED'.