Does forming an LLC protect my business name as a trademark?

No. Forming an LLC and obtaining trademark rights are separate legal matters.

An LLC registration creates a business entity. It does not automatically grant federal trademark rights.

Trademark law places marks on a spectrum of distinctiveness. In general, the more unusual and brand-specific a mark is, the easier it is to distinguish from ordinary language and the stronger it may be as a source identifier. Fanciful, arbitrary, and suggestive marks are usually stronger than merely descriptive wording, while generic terms generally cannot function as trademarks for the goods or services they name.

The USPTO evaluates the mark as a whole and in relation to the specific goods or services listed in the application. A term that is weak or descriptive in one industry may have a different meaning in another, so eligibility is highly dependent on context.