filter; wave filter
Technical term for a device or circuit that passes or blocks signals based on frequency; used in electronics and signal processing.
This circuit incorporates a filter that removes high-frequency components.
Designing a filter requires knowledge of transfer functions.
bandpass filter
Standard technical spelling using the simplified ろ for the filter component.
Traditional kanji spelling using 濾; less common in modern technical writing.
Compound of ろ (filter) and 波器 (wave device). The exact historical derivation is uncertain; the spelling is conventionally associated with electronic filtering.