Is BILLY a Wordle Word?

Yes. BILLY is a valid Wordle word.

It is on the original Wordle answer list and has not been an answer yet, so it could be a future answer.

What does BILLY mean?

3 more noun definitions

A tin used by bushmen to boil tea; a billycan; a billypot.“Let's get the billy and cook some beans.”
A condom (from the E-Rotic song "Willy, Use a Billy... Boy")
A slubbing or roving machine.

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

Starter word rating: WeakIn the top 91% of all valid Wordle words for testing common letters.
Vowels: I
Unique letters: 4 of 5Repeats L
Common letters: I, L

Hard-mode trap: 10 valid words fit the pattern _ILLY. 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.