Would radiation-release from a Nuclear-Bomb or a Nuclear-Meltdown be worse and why?

Of course a bomb is far more dangerous. An atomic bomb is made specifically to explode and distroy and kill as many people as possible. A nuclear power plant is designed for safety. It has containment structurrs and safeguards. Even in a meltdown, few if any people would be killed.

Good answers above. Don't forget the damage to other dimensions.

A dirty bomb is the worst because It spreads contamination over a very large area. A melt down is confined. 3 mi Is, Nukashima and chernoble are contained to less than 20 sq miles ea.

Fallout from nuclear bombs decays relatively quickly. Depending on the yield, an area may be safe to travel in after only 3 - 5 weeks. Of course, these aren't "dirty" bombs that are specifically designed to spread radioactive material. There wouldn't be any point in rendering a large swath of the countryside uninhabitable for thousands of years. By comparison, Chernobyl, the most well known reactor meltdown, has rendered an area of thousands of square kilometres uninhabitable for thousands of years.

Nuclear meltdown is more dangerous than the nuclear bomb explosion. The radiation cloud gets dispersed very soon. Area becomes hospitable in a short time. Where as the nuclear meltdown gets mixed with mud and sand. It will take many more years to clear. Therefore, meltdown is more dangerous.

Nuclear-Meltdown...more concentrated, then more powerful and difficult to confine

fukishima has been leaking the equivalent of a Hiroshima bomb of radiation every day for the last 6 years . the pacific is dying . we are doomed .

a bomb would throw radiation EVERYWHERE, but a melt-down would ONLY spread radiation down-wind .......................

A nuclear bomb, as it would send dirt and dust into the air, all somewhat irradiated. It would travel on the winds around the world. A meltdown really would only affect a rather small area