Face Britain used on 'head' (8)
I believe the answer is:
boldness
'face' is the definition.
('boldness' can be a synonym of 'face')
'britain used on head' is the wordplay.
'britain' becomes 'b' (common abbreviation as in GB).
'used' becomes 'old' ('old' can be similar in meaning to 'used').
'on' means one lot of letters go next to another.
'head' becomes 'ness' (ness is a headland**).
'b'+'old'+'ness'='BOLDNESS'
(Other definitions for boldness that I've seen before include "Confidence, daring" , "brass" , "Audacity" , "Courage, daring" .)