Refuse stockpile

From DwarfFortressWiki

Your dwarves will bring mostly animal items to a refuse stockpile, such as remains, bones, shells, skulls and corpses. This helps in avoiding miasma from rotting items in your fortress.

It is useful to keep a refuse stockpile either outside, where no miasma is created, or in a small, enclosed room next to your butcher's shop to store corpses waiting to be slaughtered, prevent clutter, and lock in miasma from rotting butcher leftovers. Butcher's shops tend to become cluttered very quickly, as a single large animal already provides many items.

It is also useful to keep a refuse stockpile holding only shells, skulls and bones near your craftsdwarf's shop for bone carving and bowyer's shop for making bone crossbows. Such a stockpile will not create miasma because nothing in it can rot.

You can provide your stockpile with 2 doors arranged as an airlock. This will completely prevent miasma from spreading when a dwarf steps through. Or you can places the corridors on a diagonal pattern; miasma doesn't travel on diagonals the way dwarfs and fluids do.