An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the agonist, while an inverse agonist causes an action opposite to that of the agonist. The meaning of AGONIST is one that is engaged in a struggle. How to use agonist in a sentence. agonistnoun[C] (PERSON) literature, theatre & film a protagonist (Definition of agonist from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press) agonist (A-guh-nist) A drug or substance that binds to a receptor inside a cell or on its surface and causes the same action as the substance that normally binds to the receptor. · An agonist is a chemical substance that plays a fundamental role in biological systems, influencing how cells communicate and how various bodily functions are regulated. · An agonist is a chemical messenger, or ligand, that binds to a specific receptor protein on a cell and produces a biological response. This binding event mimics the action of naturally occurring substances within the body, such as hormones and neurotransmitters. · 1. (prime mover) a muscle whose active contraction causes movement of a part of the body. Contraction of an agonist is associated with relaxation of its antagonist. 2. a drug or other substance that acts at a cell-receptor site to produce an effect that is the same as, or similar to, that of the body’s normal chemical messenger.
