micropore

/ˈmaɪkroʊˌpɔr/
noun
  1. A very tiny opening or hole in a material, often too small to be seen without a microscope.
    • Engineers designed a filter with micropores that can trap bacteria.
    • Soil with many micropores holds moisture better than sandy soil.
    • The micropores in this sponge allow it to absorb water quickly.
Synonyms
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