Are Silverfish Actually Fish?

Silverfish, also known as fishmoths, are in fact not fish at all. They are insects of the order Thysanura.

So why are they called silverfish?

There are two reasons:

1. The silvery grey or blue color of the silverfish is similar to the scales of an actual fish.

2. As silverfish move, they often exhibit a movement which is similar to that of a fish swimming through the water.