pa ‧ ram ‧ e ‧ ter AC /pəˈræmətə, pəˈræmɪtə $ -ər/ BrE AmE noun [countable usually plural]
[ Date: 1600-1700 ; Language: Modern Latin ; Origin: para- ( ⇨ ↑ para- ) + Greek metron 'measure' ]
a set of fixed limits that control the way that something should be done:
The inquiry has to stay within the parameters laid down by Congress.