Is "Playing the Stock Market" gambling?

First, let's look at some of the definitions of the word gamble.

–verb (used without object)
1. to play at any game of chance for money or other stakes.
2. to stake or risk money, or anything of value, on the outcome of something involving chance: to gamble on a toss of the dice.

–verb (used with object)

3. to lose or squander by betting (usually fol. by away): He gambled all his hard-earned money away in one night.