* Preposition: This is the most common usage. It indicates location, position, or direction, and usually comes before a noun or pronoun.
* Example: "The cat is under the table."
* Adverb: It can modify a verb, adjective, or another adverb, indicating location or position.
* Example: "The dog burrowed under the fence."
* Adjective: Though less common, "under" can act as an adjective, meaning "lower than" or "less than."
* Example: "He was under the legal drinking age."
So, the specific type of word "under" is depends on its function in the sentence.