separator

noun

1. a person or thing that separates.
2. any of various apparatus for separating one thing from another, as cream from milk, steam from water, or wheat from chaff.
3. Electricity. a device that prevents metal contact between plates of opposite charge in a storage battery.
4. Machinery. retainer1(def 3).

noun

1. a person or thing that separates
2. a device for separating things into constituent parts, as milk into cream, etc

n.c.1600, “separatist,” agent noun from separate (v.). As a mechanical device for separating, from 1831.