activity in WordNet English dictionary

1. a process existing in or produced by nature (rather than by the intent of human beings)
   "the action of natural forces"; "volcanic activity"
   natural process  natural action  action  activity 
   
2. the state of being active
   "his sphere of activity"; "he is out of action"
   action  activity  activeness 
   
3. the trait of being active; moving or acting rapidly and energetically
   "the level of activity declines with age"
   activeness  activity 
   
4. any specific behavior
   "they avoided all recreational activity"
   activity 
   
5. an organic process that takes place in the body
   "respiratory activity"
   bodily process  body process  bodily function  activity 
   
6. (chemistry) the capacity of a substance to take part in a chemical reaction
   "catalytic activity"
   activity