Take away sign created by head of McDonald's in America (5)
I believe the answer is:
minus
'take away sign' is the definition.
(minus sign in mathematics)
'head of mcdonald's in america' is the wordplay.
'head of' indicates taking the first letters.
'america' becomes 'US' (United States).
The initial letter of 'mcdonald' is 'm'.
'm'+'in'+'us'='MINUS'
'created by' acts as a link.
(Other definitions for minus that I've seen before include "'Take away' sign" , "Take-away (sign)" , "Lacking; below zero" , "deficiency" , "(Of temperature) below zero" .)