Definition of colloid in English:



  • 1A homogeneous non-crystalline substance consisting of large molecules or ultramicroscopic particles of one substance dispersed through a second substance. Colloids include gels, sols, and emulsions; the particles do not settle, and cannot be separated out by ordinary filtering or centrifuging like those in a suspension.

    • ‘He showed that these materials were long, chain-like molecules and not colloids as previously thought.’
    • ‘And 10 years later he used freezing point depressions to determine the molecular weights of colloids such as gum, Fe 3 etc.’
    • ‘This increase in cytoplasmic viscosity can be described as a sol-gel transition, which is generally explained with chemical or physical reactions of molecules, polymers, or colloids.’
    • ‘In lyophobic colloids the particle-solvent interaction is energetically unfavorable and the suspension will sooner or later separate.’
    • ‘By depositing proteins as monolayers onto gold colloids, the aim will be to develop biosensors for nitrate and nitric oxide with detection capabilities approaching those of natural bacterial cells.’
    mixture, mix, blend, compound, suspension, tincture, infusion, emulsion, gel, fluid
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    1. 1.1Anatomy Medicine mass noun A substance of gelatinous consistency.
      • ‘Radiolabeled colloid injected into the peritoneal cavity can be used to demonstrate the communication between the peritoneal and pleural space.’
      • ‘Thus, sentinel lymph nodes can be detected by the injection of blue dye or radioactive colloid around the tumor, which travels to and identifies the first draining sentinel lymph node.’
      • ‘These techniques offer advantages similar to those of haemodilution but do not require infusions of crystalloid or colloid to preserve blood volume.’
      • ‘Cell blocks revealed sheets or clusters of follicular cells and variably sized follicles filled with colloid.’
      • ‘The most common radiotracers used in GI bleeding studies are 99m-Tc labeled red blood cells and 99m-Tc sulfur colloid.’


  • Relating to or characterized by a colloid or colloids.

    • ‘The addition of neutral polymers to colloid solutions results in a nonspecific attractive potential between colloids, called the depletion attraction, dependent upon polymer size and concentration.’
    • ‘The first cancer had been diagnosed as colloid carcinoma in 1985.’
    • ‘They attributed their low colloid carcinoma detection rate to the absence of sufficient guidelines for the identification of colloid carcinoma at the time of their study.’
    • ‘This assumption is generally verified in colloid science and has been precisely verified for our material only at low concentration of monovalent salt.’
    • ‘Several previous reports have dealt with the experimental and theoretical aspects of depletion aggregation, often termed depletion flocculation, as applied to the general field of colloid chemistry.’


Mid 19th century: from Greek kolla ‘glue’ + -oid.