dermal anchor piercings?

Technically yes, there is.

Dermal anchors have one foot with a hook at the end that sits under the skin. This is a dermal anchor (scroll about half way down the page, you'll know it when you see it):

http://news.bmezine.com/2005/10/14/dermal-anchorin...

Microdermals have too feet that sit under the skin, with no hooks. They are both single point piercings. These are microdermals:

http://www.sams-piercing.ch/E_cb_18_EN_BlobMemo_2....

However, this is only a technical difference. True dermal anchors are pretty much never done; it's a personally developed technique only done by a few piercers.

When most people day dermal anchors, they mean microdermals. It's come to more or less be a synonym is casual description.

Same thing, different names. I have one on my upper chest and love it. It's a great conversation starter.

No, same thing, just different names.

Nope,small thing different name..