Tin contains soft odd Scottish pouch (7)
I believe the answer is:
sporran
'pouch' is the definition.
(sporran is a kind of pouch)
'tin contains soft odd scottish' is the wordplay.
'tin' becomes 'sn' (Sn is the chemical symbol for tin).
'contains' is an insertion indicator.
'soft' becomes 'p' (musical abbreviation for 'piano').
'odd scottish' becomes 'orra' (Scottish term for 'odd').
'p'+'orra'='porra'
'sn' enclosing 'porra' is 'SPORRAN'.
(Other definitions for sporran that I've seen before include "Pouch on Highlander's belt" , "Pouch as part of highland dress" , "Pouch worn in Scottish Highland dress" , "Purse worn with kilt" , "Pouch hanging in front of kilt" .)