As nouns the difference between scuttle and obstacle
is that
scuttle is a container like an open bucket (usually to hold and carry coal) or
scuttle can be a small hatch or opening in a boat also, small opening in a boat or ship for draining water from open deck or
scuttle can be a quick pace; a short run while
obstacle is something that impedes, stands in the way of, or holds up progress.
As a verb scuttle
is (nautical) to cut a hole or holes through the bottom, deck, or sides of (as of a ship), for any purpose or
scuttle can be to move hastily, to scurry.