high-pass filter: a filter that passes frequencies above a certain value and attenuates frequencies below that value
device: an instrumentality invented for a particular purpose
dilleniidae: a group of families of more or less advanced trees and shrubs and herbs having either polypetalous or gamopetalous corollas and often with ovules attached to the walls of the ovary; contains 69 families including Ericaceae and Cruciferae and Malvaceae; sometimes classified as a superorder