"Square" and "parallelogram" in the description of a person

[Green Bean]

Dear Sir,

I saw the following in one English textbook published in Singapore: "There was this lady Maths teacher. To her we were just mixed-up kids. To us she was not only a square but a parallelogram. She could never figure out what we would be up to next."

I can find the meaning of a square in the description of a person. But for "parallelogram", I can't. May I know what is the meaning of "parallelogram" in the above context?

Thank you.

[emsr2d2]

It's a pun. We describe people as square when we think they are not cool, hip, trendy, perhaps even that they are a bit boring. This woman was more than just square, she wasn't even a square square! "Parallelogram" is not a word we generally use to describe people in English. The author was making a joke.

[Raymott]

I still don't get it.

[5jj]

I still don't get it.

Age!

This sums it up: "This woman was more than just square, she wasn't even a square square!"

People who had outdated ideas were 'square'. Her ideas, approach to life, were so outdated that she was a distorted square.