What is gambling?

What do you think of when you hear the word "gamble"?  What do you think it really means?

My daughter asked me this question.  I had some difficulty answering her.

The first ideas that came to my mind were things like casinos, horse-races and lotteries.  Things that carry an element of risk.  A situation where one stands to lose if one does not win.  Do similar thoughts cross your mind when you think about this word?

Then how do you distinguish gambling from sports?  Business?  Saving people's lives in the case of bushfires?  These situations also carry risk, where one stands to lose if one does not win.

Furthermore is the concept of ethics; ie. where one associates gambling with an element of immorality.  Where would one draw the line between moral risks and immoral ones?  Why?  Should gambling be thought of as immoral?

The Cambridge Dictionary's definition of the word "gamble" is consistent with what I wrote above.  But it does not draw the line between what is moral and what isn't.

Then there is the issue of lucky dips, school competitions, charity sweepstakes and raffle tickets.  Is it to be considered gambling if one donates to charity when one loses?

What do you think?  How would you explain the ethics to a school girl?  What is acceptable before God?  Is the society's attitude to gambling consistent with what God expects of us?