"To sex" is to determine sex (gender.)

If someone says "I am sexing your mom" on the internet, that is definitely not what they mean.

Not me. I’m definitely checking your mom’s gender.

grammar*

What does his grandmother have to do with it?

She was the first person to check his mom's gender. Duh.

It could be, from a certain point of view.

Thank you, Obi Wan.

We're buying mice and we want 2 or 3 females. So yesterday I was searching "how to check mouse gender". Imagine my confusion when search engine recommended me a bunch of "how to sex mice" youtube videos!

Some words have multiple meanings

There’s a sign on the door but she wants to be sure…