The word deliberate is not a noun; the word deliberate is a verb (deliberate, deliberates, deliberating, deliberated), and an adjective (deliberate, more deliberate, most deliberate).

The noun forms for the verb to deliberate are deliberator, deliberation, and the gerund, deliberating.

The noun form for the adjective deliberate is deliberateness.

The noun forms function in a sentence as the subject of a sentence or a clause; and as the object of a verb or a preposition. Examples:

• Deliberating for too long may cause you to miss an opportunity.
• The district attorney, the deliberator reviewing the case, will issue his decision today.
• He applied deliberateness to completing the task.
• The board is meeting today to complete their deliberation.