This is the 225th most frequent French word.
française
The feminine form of "French" or "Frenchwoman."
Here 'française' is an adjective modifying 'langue', explaining the specific type of language being referred to as French.
Je parle couramment la langue française.
I fluently speak the French language.
In this context, 'française' acts as an adjective describing 'baguette', specifying that it is a French-style baguette.
Elle a acheté une baguette française ce matin.
She bought a French baguette this morning.
Here, 'Française' is used as a noun to denote a person (specifically a woman) of French nationality.