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colloid

n.

1. a large, gluelike molecule that cannot pass through the plasma membrane of a cell. When injected into the peritoneum, colloids attract and retain water by osmosis.

2. a system consisting of two or more phases in which one phase (the dispersed phase) is distributed throughout the other phase (the continuous phase). A sol, for example, consists of large molecules or small solid particles distributed in a liquid, as when starch is mixed with water. —colloidal adj.

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Psychology term of the day

March 16th 2025

imipramine

imipramine

n. a tricyclic antidepressant (TCA) with a tertiary amine molecular structure. It was originally synthesized in the hope of creating an effective antipsychotic but was observed to be ineffective in reducing psychotic symptoms. It did, however, seem to help individuals with severe depression and was subsequently marketed as an antidepressant. It is considered the prototype TCA, and like all tricyclic agents, its use as an antidepressant has been largely supplanted by less toxic drugs. It retains a therapeutic role as a sedative and adjunct in the management of neuromuscular or musculoskeletal pain. U.S. trade name: Tofranil.