In English grammar, a nominative absolute is a free-standing (absolute) part of a sentence that describes or modifies the main subject and verb. It is usually at the beginning or end of the sentence, although it can also appear in the middle. Its parallel is the ablative absolute in Latin, or the genitive absolute in Greek.
One way to identify a nominative absolute is to add a verb; one can always create a sentence out of a nominative absolute by adding one verb (generally a form of to be).
Similarly, one can break the absolute off, add a verb and make two sentences. For example, Stephen searched frantically for a dictionary. His mind was taxed.
A prominent example of a nominative absolute is the sentence composing the Second Amendment to the United States Constitution: