English Meaning: The name Kelsie is an English baby name. In English the meaning of the name Kelsie is: Brave. American Meaning: The name Kelsie is an American baby name.In American the meaning of the name Kelsie is: Brave.SoulUrge Number: 1. Expression Number: 7. People with this name have a deep inner desire to use their abilities in leadership, and to have personal independence. They would rather focus on large, important issues, and delegate the details.n American the meaning of the name Kelsie is: Brave. SoulUrge Number: 1. Expression Number: 7. People with this name have a deep inner desire to use their abilities in leadership, and to have personal independence. They would rather focus on large, important issues, and delegate the details.