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Medical Dictionary


noun col·loid \ˈkäl-ˌid\

Medical Definition of COLLOID

:  a gelatinous or mucinous substance found in tissues in disease or normally (as in the thyroid)
a :  a substance consisting of particles that are dispersed throughout another substance and are too small for resolution with an ordinary light microscope but are incapable of passing through a semipermeable membrane b :  a mixture (as smoke) consisting of a colloid together with the medium in which it is dispersed
col·loi·dal \kə-ˈlid-əl, kä-\ adjective
col·loi·dal·ly \-əl-ē\ adverb
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