Perhaps Collins can start to explain including Iceland's word meaning vulgarian? (10)
I believe the answer is:
philistine
'word meaning vulgarian?' is the definition.
'perhaps collins can start to explain including iceland's' is the wordplay.
'perhaps collins' becomes 'phil' (Phil Collins).
'can' becomes 'tin' ('tin' can be a synonym of 'can').
'start to' says to take the initial letters.
'including' means one lot of letters goes inside another.
'iceland' becomes 'is'.
The first letter of 'explain' is 'e'.
'phil'+'tin'+'e'='philtine'
'philtine' placed around 'is' is 'PHILISTINE'.
(Other definitions for philistine that I've seen before include "one who's lowbrow?" , "One hostile to culture" , "One indifferent to culture" , "Tasteless" , "Someone indifferent to culture and the arts" .)