"Retriggering" is basically when you set off another round of free spins while playing in free spins mode. This is usually accomplished by lining up the same special symbols that launched you into free spins mode initially. When you retrigger, you get a whole new round of free spins, which potentially doubles the amount of wager-free earnings you'll enjoy at the end of your free spins round.

Free spins and retriggers are activated by hitting 3 or more scatter symbols. Pictured is the free spins trigger for Kitty Glitter by IGT.

In theory, respinning can occur more than once in a set of free spins. However, most slot makers but a cap on the max number of free spins you can earn in any one round. So while you can retrigger several times, the max times is generally around 5-10, though given the?odds of this happening, it is a rare occurence.

Sometimes free spins are part of a bonus that is activated in any way in which a game’s developer chose to set forth. Sometimes a game says that a bonus cannot be retriggered during free spins, simply meaning that more spins are not possible while the bonus round is activated.

Retriggering is a fun, effortless way to rack up some serious coins without having to bet anything first, so it's worth looking for games that include this feature. It is easy to find out if a game offers retriggering - just check out the paytable ahead of time. If retriggering isn't mentioned, it is probably safe to assume that the game doesn't offer it.