The word "sunrise" is a noun. It refers to the daily event of the sun appearing above the horizon in the morning. As a noun, it can function as the subject or object of a sentence, and it can be modified by adjectives or other determiners. For example:

• "The sunrise was breathtaking." (Subject)
• "We watched the sunrise from the beach." (Object)
• "The golden sunrise painted the sky." (Modified by an adjective)

Nouns like "sunrise" often represent concrete or abstract entities, and in this case, "sunrise" is a concrete noun because it refers to a specific, observable event.