proviso
Concise Oxford English Dictionary © 2008 Oxford University Press:
proviso /prəˈvʌɪzəʊ/
▶noun (pl. provisos) a condition or qualification attached to an agreement or statement.
– origin ME: from the med. L. phr. proviso (quod) ‘it being provided (that)’.
'proviso' also found in these Oxford entries:

