secundo-geniture

from The Collaborative International Dictionary of English v.0.48

Secundo-geniture \Se*cun`do-gen"i*ture\, n. [L. secundus second
   + genitura a begetting, generation.]
   A right of inheritance belonging to a second son; a property
   or possession so inherited.
   [1913 Webster]

         The kingdom of Naples . . . was constituted a
         secundo-geniture of Spain.               --Bancroft.
   [1913 Webster]