French bread

From French +‎ bread. From being the stereotypical type of bread associated with France.

French bread (usually uncountable, plural French breads)

1. (informal) Synonym of baguette: a long thin loaf of bread with a thick crust and often having large bubbles of air inside, popular in and associated with France.
2. Used other than figuratively or idiomatically: see French,‎ bread.
   • 2016, Sarah Black, One Dough, Ten Breads: Making Great Bread by Hand, page 62:

     Boule refers to the shape of the traditional French breads—puffed rustic rounds scored by the village baker.