senonian

from The Collaborative International Dictionary of English v.0.48

Senonian \Se*no"ni*an\, a. [F. s['e]nonien, from the district of
   S['e]nonais, in France.] (Geol.)
   In european geology, a name given to the middle division of
   the Upper Cretaceous formation.
   [1913 Webster] Senyor