Webster's 1828 Dictionary
RUBICAN
a.[L. rubeo, to be red. ] Rubican color of a horse, is a bay, sorrel or black, with a light gray or white upon the flanks, but the gray or white not predominant there.
Webster's 1913 Dictionary
RUBICAN
Ru "bi *can, a. Etym: [F.]
Defn: Colored a prevailing red, bay, or black, with flecks of white or gray especially on the flanks; -- said of horses. Smart.
Spanish Dictionary
rubicán, -cana
rubicán, -cana adjetivo [caballería ] Que tiene el pelaje mezclado de rojo y blanco .
The Wordsmith Dictionary