means A person who operates an aircraft, ship, or other vehicle — or, as an adjective, something done as a trial run before the full thing.

from From the Italian 'pilota,' which traces back through Medieval Latin to a Greek root 'pedon,' meaning the blade of an oar or a rudder — so the original pilot was a steersman of ships, not a flier of planes. The word kept to the sea for centuries; only in the early 20th century, when humans took to the air, did it climb into the cockpit. The 'trial run' sense (a pilot episode, a pilot program) is more recent still, borrowing the idea of someone who guides a venture into uncharted waters.