"Squarish" means somewhat square in shape, but not perfectly square. It describes something that has a resemblance to a square, but is slightly different in proportions.
Slightly kidney - shaped with squarish ends, cannellini beans are from Italy and are creamy white... (bbcgoodfood.com)
Galaxy Note 8 is Samsung's first smartphone with Dual Camera and it features an infinity display just like the Galaxy S8 + but has a more squarish design. (phonehorn.com)
What this means is the iPad is more squarish in shape while the Galaxy Tab is more rectangular. (goodereader.com)