What is the antonym for astounding?

The antonym for astounding depends on the context, but here are some possibilities:

General Antonyms:

* Ordinary

* Unremarkable

* Boring

* Unimpressive

* Mundane

* Uninteresting

* Commonplace

Specific Antonyms (depending on context):

* Disappointing (if something was expected to be astounding but wasn't)

* Unbelievable (if something is so unbelievable that it's not astounding)

* Predictable (if something was expected and not surprising)

Example:

* Astounding: "The view from the mountaintop was astounding."

* Antonym: "The view from the highway was ordinary."

It's best to consider the specific situation and choose an antonym that best fits the meaning you want to convey.