Hadley is an Old English place name and surname — from hǣð (heather) and lēah (clearing, meadow). The original sense is a meadow covered in heather. The name appears in English records from the medieval period as a surname.
Hadley has been used as a first name since the 2000s, particularly in the U.S., where it now sits in the top 120. The actress Daisy Ridley's character in the Star Wars films is not Hadley — but the name belongs to the same modern wave of surname-as-first-name choices.
Hadley reduces to nine — the number of generosity and quiet completion.