Flotsam is debris from a wrecked ship that floats on the ocean's surface. When a vessel sinks or breaks apart in a storm, pieces of cargo, wood from the hull, life preservers, and other objects drift away on the waves. This floating wreckage is flotsam.

Historically, maritime law treated flotsam differently from jetsam, which is cargo deliberately thrown overboard to lighten a ship in danger. Flotsam floated away by accident, while jetsam was tossed on purpose. Beachcombers sometimes find flotsam washed up on shore after storms, discovering interesting remnants of shipwrecks that might have traveled thousands of miles across the ocean.

Today people often use “flotsam and jetsam” together as a phrase meaning random odds and ends or discarded items. You might hear someone describe the random objects in a cluttered garage as flotsam and jetsam. The phrase can also refer to people who drift through life without direction or purpose, though this usage is less common. When you see driftwood, plastic bottles, or other debris floating in a harbor, you're looking at modern flotsam, even if it didn't come from a shipwreck.