A biosynthetic limb is a prosthetic limb made for patients who had lost limbs through injury or disease.
In 2375 Nog received a biosynthetic limb to replace the leg he lost at AR-558. (DS9 episode: "The Siege of AR-558")
In 2376 three persons were shipped out from Deep Space 9 to Starbase 235 to receive biosynthetic limbs after being injured in a Jem'Hadar attack on the station. (DS9 novel: Avatar)
Following the near-tragedy at Galvan VI, USS da Vinci Captain David Gold received a biosynthetic replacement for his lost left hand. (SCE eBook: Aftermath)