Look at this woman's face. If you recognize her, think about how you'd say her name, then read on:

Got it?

Well, you might be wrong.

She's Sacagawea, the Native American woman best known for her role in the renowned westward expedition of Lewis & Clark, and for her likeness imprinted on that special edition piece of U.S. currency.

Washington University in St. Louis history professor Peter Kastor has focused his research on the time surrounding the Louisiana Purchase - listen to Kastor explain how he says Sacagawea's name and why:

Interesting, right? Check out the rest of the conversation about the role Meriwether Lewis and William Clark played in the formation and governance of the St. Louis region on St. Louis on the Air.