What Part of Speech is a Number? Posted on July 9, 2021August 3, 2021 by Cozy Grammar Ask Cozy Grammar Liam from Meridian, Idaho, asks, "What part of speech is a number in a sentence?" Here Thomas explores how numbers sometimes serve as adjectives or determiners, and sometimes serve as nouns. It all depends on the context of the sentence. EXPLORE OUR LEARNING TREASURE TROVE ASK THOMAS A QUESTION OF YOUR OWN