utter nonsense
complete nonsense

All that utter nonsense about the Ship being capable of moving.

That was utter nonsense; no one with any intelligence would ever believe it.

This is utter nonsense and just goes to show how little the average person knows about politics.

The utter nonsense is not limited to the last section, however.

He said of the report, "That sounds like utter nonsense to me."

It's utter nonsense and no one is going to believe you.

In fact, you can speak utter nonsense and it will just do stuff.

It was one thing not to be able to think of anything - but how could he possibly come out with utter nonsense?

Not going to get in to a debate about immigration here, but this is just utter nonsense.

"They supported me at a time when people thought that my work was utter nonsense," he says.