The Collaborative International Dictionary of English v.0.48:

Daimio \Dai"mi*o\, n.; pl. Daimios. [Jap., fr. Chin. tai ming
   great name.]
   The title of the feudal nobles of Japan.
   [1913 Webster]

         The daimios, or territorial nobles, resided in Yedo and
         were divided into four classes.          --Am. Cyc.
   [1913 Webster]