with the grain

[석수]

고기 결대로 : with the grain
고기결 반대로 : against the grain 


https://www.getwellseasoned.com/blogs/news/slicing-steaks-going-against-the-grain

Slicing Steaks (And Other Meats): Going Against The Grain

Did you know that how you cut your meats directly affects its tenderness? The reason is because muscle fibers run in a specific direction, and the longer those fibers in the piece of meat you're eating the less tender it will be. This alignment of the muscle fibers is called the "grain" of that piece of meat, and the goal is to cut across the grain to shorten those fibers as much as possible and thus increase the tenderness of the steak.
In the image above, you can clearly see the direction the fibers are aligned on a piece of steak. This is easier to see in some steaks than others, and is also more visible before they are cooked. Once you've identified the direction of the grain, you'll want to slice perpendicular to that grain, whether you're slicing the steak on your own plate or ahead of time if you are cutting a larger steak to share with others.

along the grain

across the grain