Word.ws English Dictionary

underfilter

underfilter noun: a morphological filter (idempotent operator) whose image is a subset of the domain.

Noun

underfilter (plural underfilters)

  1. A morphological filter (idempotent operator) whose image is a subset of the domain.
    • It is clear that overfilters and underfilters are dual in the sense of the duality principle.1999, Edward R. Dougherty, Jaakko Astola, Nonlinear Filters for Image Processing, page 180
  2. A filter that is positioned beneath something.
    • The paving downstream consisted of 18x18x8-inch blocks laid on edge over a brick base which in turn was underlain with a gravel or brick chip filter. Since there was some controversy as to whether an underfilter was necessary, the first test was made with the filter omited.^([sic])1967, Journal of the Institution of Engineers Pakistan
    • Since there is no underfilter, the top flow line emerges on the downstream slope.1988, Árpád Kézdi, László Rétháti, Handbook of Soil Mechanics, page 61

Verb

underfilter (third-person singular simple present underfilters, present participle underfiltering, simple past and past participle underfiltered)

  1. To filter insufficiently.
    • It is not possible to overfilter your tank but marine aquaria are frequently underfiltered.1966, William P. Braker, Know how to Keep Saltwater Fishes, page 19
    • You don't want to underfilter. Nor do you want to filter beyond what is economically justifiable.1978, Hydraulics and Pneumatics

Examples of underfilter in a sentence

  • A single sheet of filter paper is used as an underfilter.1992, Margaret M. Manson, Immunochemical Protocols, page 445:
  • In addition, the flow from the underfilter, which had previously been clear, became cloudy, indicating that the filter had failed to block particles from the core.2004, R.F. Craig, Craig's Soil Mechanics, →ISBN, page 430:
  • Underfiltering by using too high a cut-off frequency leaves too much noise in the reconstructed images (bottom row).1994, Douglas Van Nostrand, Selected Atlases of Cardiovascular Nuclear Medicine, →ISBN, page 35:

Forms of underfilter

Noun
pluralunderfilters
Verb
third-person singular presentunderfilters
present participleunderfiltering
past participleunderfiltered
pastunderfiltered

Origin of underfilter

From under- + filter.

Questions about underfilter

What does underfilter mean?
Underfilter means a morphological filter (idempotent operator) whose image is a subset of the domain.
How do you use underfilter in a sentence?
A single sheet of filter paper is used as an underfilter.
What part of speech is underfilter?
Underfilter can be a noun or a verb.
What is the plural of underfilter?
The plural of underfilter is underfilters.

Words near underfilter in the dictionary

  1. underfill
  2. underfilled
  3. underfilling
  4. underfillings
  5. underfills
  6. underfilter
  7. underfiltered
  8. underfiltering
  9. underfilters
  10. underfinance
  11. underfinanced

Source and license

Adapted from Wiktionary: underfilter (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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Pronunciation audio from Wikimedia Commons, each file under its own free license: LL-Q1860 (eng)-Flame, not lame-underfilter.wav.

Cite this entry: “underfilter.” Word.ws, https://word.ws/underfilter. Based on Wiktionary, CC BY-SA 4.0.