Digi-Modify

Digi-Modify (カード・スラッシュ) is the term used in Digimon Tamers to refer to the act of modifying a partner Digimon's capabilities through the use of the Japanese Digital Monster Card Game.

Concept
In Digimon Tamers, Digimon normally have to absorb data to get stronger. A Digimon partnered with Tamers on the other hand has the capability to temporarily increase its power using cards scanned through the Tamer's D-Power. This act looks like the Tamer is "slashing" their card through the Digivice, hence the Japanese term "Card Slash".