What part of speech is the word using?

The word "using" is a present participle. It's a verb form that acts as an adjective or adverb.

Here are some examples:

* Adjective: "The using device is broken." (Describes the device)

* Adverb: "She was using a hammer to fix the fence." (Modifies the verb "was")

It's important to note that "using" is not a verb on its own. It's a part of a verb phrase, like "is using" or "was using."