Bounce has 2 meanings
Return a card to a player's hand
I'll bounce your Grizzly Bears with Echoing Truth and attack.
|Removal||A card that can destroy or nullify an opponent's card|
|Topdeck||To draw from your deck|
|Card advantage||Possessing more cards than another player|
|Trade||Destroy or counter an opponent's card with your own|
|ETB||Enters the battlefield|
|Board clear||Move that clears the opponent's board of minions|
|Aggro deck||Aggressive card deck|
|CCG||Collectible card game|
|TCG||Trading card game|
|MTG||Magic: The Gathering|
Bounce is another way to say that you are leaving. For example, when exiting a party or an online message thread, you might say, "It's been real. Gotta bounce."
The term gained popularity in the early 2000s, mainly because the rap community made it cool to say. People then adopted it to use whenever they were leaving an actual gathering, a relationship, or even a virtual meeting, such as a text thread or online chatroom.
Bounce is just one way to say that you are leaving. Other options include dip, jet, rollout, and gotta blast.
This party sure died, you wanna bounce?
|TTL||Time to leave|
|G2R||Got to run|
|t2go||Time to go|
|GGOH||Gotta get out of here|
|Gotta blast||Have to leave|
In Hearthstone, Magic: The Gathering (MTG), and other CCGs, to bounce a card means to return it from the battlefield to its owner's hand. For example, the MTG card Unsummon allows you to bounce an in-play creature (and is MTG's most iconic bounce spell).
There are many reasons a player might want to bounce an in-play card (usually a minion or creature) to their own or their opponent's hand. When used on an opponent's creature, a bounce spell acts as a soft removal spell, buying time in which you can either defeat your opponent or topdeck a permanent answer to their creature. Using a bounce spell on your own creature can protect it from your opponent's removal or allow you to re-use the creature's Battlecry or "enters the battlefield" (ETB) ability.
What is the difference between a bounce spell and a blink spell?
In MTG, bounce spells and blink spells are similar yet different. A bounce spell returns a card to its owner's hand, while a blink spell causes a card to temporarily leave and then re-enter the battlefield. However, a blinked card never returns to its owner's hand and does not have to be replayed. This makes blink spells a better choice than bounce spells for abusing "enters the battlefield" abilities.