gamble
verb
[no object]
1 play games of chance for money; bet:
he gambles on football
[with object] bet (a sum of money):
they gambled their money on cards
2 take risky action in the hope of a desired result:
he was gambling on the success of his satellite TV channel
noun
[usually in singular]
1 an act of gambling.
2 a risky action undertaken with the hope of success:
we decided to take a gamble and offer him a place on our staff
Origin:
early 18th century: from obsolete gamel 'play games', or from the verb game
http://www.oxforddictionaries.com/view/entry/m_en_gb0325700#m_en_gb0325700
From the first definition, any
game that involves at least some element of chance and the wagering of money on the outcome, is gambling. This would include poker, sports betting, bingo, paper rock scissors (for money), even picking/buying-selling stocks.
I think most people consider gambling as the last definition listed-
a risky action undertaken with the hope of success. I think it could very easily be argued that a player who demonstrates skill at the game over a large sample can greatly reduce the element of risk/chance sufficiently for this definition to no longer hold for them.
Examples of gambling in poker:
1- Players chasing draws with the wrong odds or regardless of the odds they are getting, whether they understand the odds or not.
2- Players playing above their
bankroll and/or skill level hoping to win
Examples of poker that aren't really gambling:
1- Players making the appropriate +EV plays in
hands
2- Players playing within their bankroll as to minimize their risk of ruin (going broke)
Another key aspect of this definition of gambling keys in on the word
"hope". Players that are "hoping" to win are gambling. Players who can use their knowledge and skills (mathematical and/or psychology and/or memory and/or experience) to produce consistent results, aren't really gambling.
Reread that last paragraph thinking in terms of stock picking and you'll see that it's virtually the same as poker. If you are good at it, much of the uncertainty/hoping is removed, as is the "gamble" of it. If you aren't good at it, you're basically gambling.