"Large square" refers to a shape that has four equal sides and four right angles that are bigger than normal or usually bigger in size. Full definition
Place a second large square of foil underneath the pan, and repeat, gently folding up the sides of the foil around the pan and pressing the foil against the pan. (simplyrecipes.com)
For example, I knew that houses with larger square footage tended to have higher prices. (entrepreneur.com)
The clean lined vanity with large square pulls are the best! (simplifiedbee.com)