Hobbies

I would love someone to give us a good definition of hobby.

Hobbies include:

• Collecting
• Book collecting
• Card collecting
• Coin collecting
• Comic book collecting
• Currency collecting
• Stamp collecting
• Gardening
• Antiquing (what's the word?)
• Cooking of course
• MuSic
• Minature wargaming
• Model-building
• Coding
• Adding stuff to Wikipedia

Etc.