One making beastly noise shelters against railing (10)
I believe the answer is:
Here is my best explanation:
'railing' is the definition.
('inveigh' can be a synonym of 'rail')
'one making beastly noise shelters against' is the subsidiary indication.
'one' becomes 'i' (Roman numeral).
'making beastly noise' becomes 'neighing'.
'shelters' means one lot of letters goes inside another.
'against' becomes 'v' (abbreviation for 'versus').
'neighing' enclosing 'v' is 'nveighing'.