vocabulary - I need a word to describe the quality of a rectangle that is upright - English Language & Usage Stack Exchange

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

Used Book in Good Condition

The Official SCRABBLE Players Dictionary

Shorter Oxford English Dictionary: 9780199206872: Oxford Languages: Books

Irreverent Definition Print

Evaluating A Dictionary

word request - Rectangle Adjectives - English Language Learners Stack Exchange

Swing Trading: Definition and the Pros and Cons for Investors

Banished Words Listed By Year 1976 - 2022

Rectangle synonyms - 154 Words and Phrases for Rectangle

Haven Definition Print

Use Case Diagram Tutorial (Guide with Examples)

RLAIF: Scaling Reinforcement Learning from AI feedback