Source : Webster's Revised Unabridged Dictionary (1913)

Buckeye \Buck"eye`\, n.
   1. (Bot.) A name given to several American trees and shrubs
      of the same genus ({[AE]sculus}) as the horse chestnut.

   {The Ohio buckeye}, or {Fetid buckeye}, is {[AE]sculus
      glabra}.

   {Red buckeye} is {[AE]. Pavia}.

   {Small buckeye} is {[AE]. paviflora}.

   {Sweet buckeye}, or {Yellow buckeye}, is {[AE]. flava}.

   2. A cant name for a native in Ohio. [U.S.]

   {Buckeye State}, Ohio; -- so called because buckeye trees
      abound there.

Source : WordNet®

buckeye
     n 1: the inedible nutlike seed of the horse chestnut [syn: {horse
          chestnut}, {conker}]
     2: tree having palmate leaves and large clusters of white to
        red flowers followed by brown shiny inedible seeds [syn: {horse
        chestnut}, {Aesculus hippocastanum}]
     3: a resident of Ohio [syn: {Ohioan}]