Caledonian street houses the company (4)
I believe the answer is:
scot
'caledonian' is the definition.
(I've seen this before)
'street houses the company' is the wordplay.
'street' becomes 'st'.
'houses' is an insertion indicator.
'the company' becomes 'co' (abbreviation).
'st' going around 'co' is 'SCOT'.
(Other definitions for scot that I've seen before include "Eg, Glasgow native" , "Native of Inverness" , "Northerner; old tax" , "Glaswegian perhaps" , "Native of Glasgow, say" .)