Definition of semipermeable in English:

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Pronunciation: /ˌsemēˈpərmēəb(ə)l/
Pronunciation: /ˌsemīˈpərmēəb(ə)l/


(Of a material or membrane) allowing certain substances to pass through it but not others, especially allowing the passage of a solvent but not of certain solutes.
Example sentences
  • In dialysis a solution is passed over a semipermeable membrane, allowing solutes up to a certain size (but not larger molecules) to diffuse across the membrane to a second solution.
  • A semipermeable membrane allows small solvent molecules to pass through, but not the larger solute molecules.
  • Graham found that the rate at which some substances, such as inorganic salts, pass through a semipermeable membrane is up to 50 times as great as the rate at which other substances, such as proteins, do so.

For editors and proofreaders

Syllabification: sem·i·per·me·a·ble

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