Is HALLS a Wordle Word?

Yes. HALLS is a valid Wordle word.

It is not on the Wordle answer list, so it is unlikely to be a daily answer.

Plurals ending in S are almost never chosen as Wordle answers.

What does HALLS mean?

A corridor; a hallway.“The drinking fountain was out in the hall.”
A meeting room.“The hotel had three halls for conferences, and two were in use by the convention.”
A manor house (originally because a magistrate's court was held in the hall of his mansion).“The duke lived in a great hall overlooking the sea.”

5 more noun definitions

A building providing student accommodation at a university.“The student government hosted several social events so that students from different halls would intermingle.”
The principal room of a secular medieval building.
Cleared passageway through a crowd, as for dancing.
A place for special professional education, or for conferring professional degrees or licences.“a Divinity Hall; Apothecaries' Hall”
A living room.

Definition from Wiktionary, available under the CC BY-SA license.

Starter word rating: WeakIn the top 64% of all valid Wordle words for testing common letters.
Vowels: A
Unique letters: 4 of 5Repeats L
Common letters: A, L

Hard-mode trap: 10 valid words fit the pattern _ALLS. If you reach it, you may need several guesses to find the last letter.

Letter ratings use how often each letter appears in Wordle answers.

Tap its tiles to the colours Wordle showed, and the Wordle Solver lists every word that still fits, with the best next guess.