William Blakeney is a character in Master and Commander: The Far Side of the World. He is a young midshipman, perhaps 11-13 years old. During the Surprise's first encounter with the Acheron, Blakeney suffers a badly broken arm. His arm is later amputated by Stephen Maturin to save his life.
Brave and serious despite his youth and small stature, Blakeney is shown to care deeply for his crewmates, particularly fellow midshipman Peter Miles Calamy and Stephen Maturin, whom he looks up to. He tells Stephen that, like Stephen, he would like to become a "fighting naturalist".
In the boarding of the Acheron, Blakeney first takes command of the Surprise under Jack Aubrey's orders, then leads an ad-hoc boarding party onto the Acheron and participates in the fighting despite his missing arm.