[kol-oid] /ˈkɒl ɔɪd/
Physical Chemistry. a substance made up of a system of particles with linear dimensions in the range of about 10 −7 to 5 × 10 −5 cm dispersed in a continuous gaseous, liquid, or solid medium whose properties depend on the large specific surface area. The particles can be large molecules like proteins, or solid, liquid, or gaseous aggregates and they remain dispersed indefinitely.
Compare , , , 4 , .
Medicine/Medical. a substance in the body, as a stored secretion or a cyst.
Physical Chemistry. .
Also called colloidal solution, colloidal suspension. a mixture having particles of one component, with diameters between 10–7 and 10–9 metres, suspended in a continuous phase of another component. The mixture has properties between those of a solution and a fine suspension
the solid suspended phase in such a mixture
(obsolete) a substance that in solution does not penetrate a semipermeable membrane Compare crystalloid (sense 2)
(physiol) a gelatinous substance of the thyroid follicles that holds the hormonal secretions of the thyroid gland
(pathol) of or relating to the gluelike translucent material found in certain degenerating tissues
of, denoting, or having the character of a colloid
1847, from French colloide (1845), from Greek kolla “glue” + -oeides “form” (see -oid).
colloid col·loid (kŏl’oid’)
Of, relating to, containing, or having the nature of a colloid.col·loi’dal (kə-loid’l, kŏ-) adj.
A mixture in which very small particles of one substance are distributed evenly throughout another substance. The particles are generally larger than those in a solution, and smaller than those in a suspension. Paints, milk, and fog are colloids. Compare solution, suspension.
A substance made up of particles that are larger than most molecules; these particles do not actually dissolve in substances but stay suspended in them.
Note: Fog, paints, and foam rubber are colloids.
- Colloid acne
colloid acne n. Colloid degeneration of the elastic tissue of the dermis due to repeatedly exposure to sunlight over a period of many years. Also called actinic elastosis, elastosis colloidalis conglomerata.
[kuh-loid-l] /kəˈlɔɪd l/ adjective, Physical Chemistry. 1. pertaining to or of the nature of a : colloidal gold and silver. /ˌkɒˈlɔɪdəl/ adjective 1. of, denoting, or having the character of a colloid adj. 1861, from colloid + -al (1).
- Colloidal gel
colloidal gel n. A colloid that has developed resistance to flow because of chemical or thermal change.
- Colloidal solution
colloidal solution n. See disperse system.