vocabulary - I need a word to describe the quality of a rectangle

I would like a more formal word that describes the rectangle on the left as opposed to the slanted one on the right. For some reason, I can't seem to think of a description without being wordy

World Bank Publications on X: Kick off #WomensMonth with a fun challenge! 🎉 We've hidden words that describe women and girls in the puzzle below. 🔍 Spot them? Share your finds in

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