upper in WordNet English dictionary

1. a central nervous system stimulant that increases energy and decreases appetite; used to treat narcolepsy and some forms of depression
   amphetamine  pep pill  upper  speed 
   
2. piece of leather or synthetic material that forms the part of a shoe or boot above the sole that encases the foot
   "Uppers come in many styles"
   upper 
   
3. the higher of two berths
   upper berth  upper 
   

1. higher in place or position
   "the upper bunk"; "in the upper center of the picture"; "the upper stories"
   upper 
   
2. superior in rank or accomplishment
   "the upper half of the class"
   upper 
   
3. the topmost one of two
   upper