Is revision a noun

Yes, the noun 'revision' is a common, uncountable, abstract noun as a Word for the process of changing, improving, or making additions to something.

The noun 'revision' is a common, singular, abstract noun as a Word for a change, improvement, or addition to something.

The noun 'revision' is a common, singular, concrete noun as a Word for a written work that has been changed, improved, or added to.