One initially unwilling to ring the Italian about waterproof material (8)
I believe the answer is:
oilcloth
'waterproof material' is the definition.
(I've seen this before)
'one initially unwilling to ring the italian about' is the wordplay.
'initially' suggests taking the first letters.
'unwilling' becomes 'loth' (similar in meaning).
'to ring' indicates putting letters inside.
'the italian' becomes 'il' (the in Italian).
'about' becomes 'c' (abbreviation for 'circa').
The initial letter of 'one' is 'o'.
'o'+'loth'='oloth'
'il'+'c'='ilc'
'oloth' enclosing 'ilc' is 'OILCLOTH'.
(Other definitions for oilcloth that I've seen before include "This floored" , "Waterproof material" , "not to be used for watercolours!" , "Fabric good in rain" , "Canvas" .)