definition of
activity

[1] #1 activity n. any specific behavior; "they avoided all recreational activity". wn

[2] #2 activity n. [action, activeness] the state of being active; "his sphere of activity"; "he is out of action". wn

[3] #3 activity n. [bodily process, body process, bodily function] an organic process that takes place in the body; "respiratory activity". wn

[4] #4 activity n. (chemistry) the capacity of a substance to take part in a chemical reaction; "catalytic activity". wn

[5] #5 activity n. [natural process, natural action, action] a process existing in or produced by nature (rather than by the intent of human beings); "the action of natural forces"; "volcanic activity". wn