alias
assumed name
false name

I believe he gave a false name from the beginning.

Some doctors order the test under a false name, he said.

I couldn't understand why he had given me a false name.

If he'd had sense enough to give them a false name.

The court decided that someone had given a false name.

They had no idea who I was and gave me three months under my false name.

You didn't even have the sense to use a false name.

It seemed to me he thought I was giving him a false name.

He gave the number of the pay phone and a false name.

He wanted to open it under a false name, but that's no longer possible.