medūza in English:

These creatures evolved from simpler organisms like jellyfish.

"A huge jellyfish! It was hovering in the water.

It hurts when a jellyfish stings you.

There are jellyfish out there today, so watch out.

If you go swimming, watch out for jellyfish ‐ they can sting you!

Mark is a jellyfish so he won't be able to do twenty push ups.

... could say," Imagine a jellyfish waltzing in a library...