Treat can be a noun, as in, "Her mother promised her a treat if she was quiet during the class." It can also be a verb, as in, "After class, her mother treated her to an ice cream because she was quiet."
In America it is quite common to treat articles (the, a, an) as a part of speech.
The word "candy" can be a noun or a verb. As a noun, it refers to a sweet treat. As a verb, it means to treat someone with excessive indulgence or desire.
Treat can be a noun, as in, "Her mother promised her a treat if she was quiet during the class." It can also be a verb, as in, "After class, her mother treated her to an ice cream because she was quiet."
In America it is quite common to treat articles (the, a, an) as a part of speech.
part of speech
The part of speech for this particular word is a noun.
The part of speech for "answer" is a noun.
adverb
what part of speech is beneath
The part of speech for "explicit" is an adjective.
The part of speech for "twirl" is a verb.
The part of speech for "unfamiliar" is an adjective.