What is the use for at? At is a preposition. We use at to refer to time or place. We also use it to refer to activities.
What is at in a sentence? The Preposition ‘At’
A preposition is a relationship word, or “connector.” It’s the sort of word that can explain the place, time, or relationship of a sentence and link the words together. In the case of the preposition at, it expresses a specific location, time or position. For example: Joe is waiting at home.
What is the meaning of symbol at? On the Internet, @ (pronounced “at” or “at sign” or “address sign”) is the symbol in an E-mail address that separates the name of the user from the user’s Internet address, as in this hypothetical e-mail address example: firstname.lastname@example.org.
Is at an noun? At can be a preposition or a noun.