restrained in WordNet English dictionary

1. prudent
   "guarded optimism"
   guarded  restrained 
   
2. marked by avoidance of extravagance or extremes
   "moderate in his demands"; "restrained in his response"
   moderate  restrained 
   
3. not showy or obtrusive
   "clothes in quiet good taste"
   quiet  restrained 
   
4. under restraint
   restrained 
   
5. cool and formal in manner
   restrained  reticent  unemotional