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A muscle that assists a prime mover muscle in performing a specific action.
A material that enhances the effect of another material so that when they are combined the total effect is greater than the sum of their individual effects.



(1) In anatomy and physiology, a muscle (or group of muscles) that acts jointly and functions homogeneously with another muscle (or group of muscles) in the same movement.

Examples of synergists in mammals (including humans) are the external intercostal and intercartilagtnous muscles and the muscles of the diaphragm, which, by contracting simultaneously, ensure the act of inhalation. Muscles that act together in performing a particular movement may be antagonists in the execution of other movements. The phenomenon of synergism is ensured by the regulatory activity of the central nervous system.

(2) In pharmacology, one of several medicinal agents used jointly whose combined effect on the body exceeds the effect exerted by each separately. Direct synergists act on the same reactive systems of the body, such as the simultaneous influence of two adrenomimetic substances. Indirect synergists exert the same end effect but differ in their mechanisms of action. For example, adrenaline and atropine act along different pathways to produce dilatation of the pupils; when taken together, the overall effect of these substances on the pupil exceeds the effect of each separately.

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The addition of an antioxidant synergist to the CR compound further improves the aging.
Offers Firebrake ZB synergist for halogen and nonhalogen flame-retardant formulations.
Flamestab NOR116 can also be used as a synergist with traditional FR products in molded polypropylene.
Table 4 presents a comparison of four of the better persistent primary antioxidants with and without a synergist in a modified black-loaded compound.
Especially significant is that good performance can be achieved without synergists such as pentaerythritol.
The company says that Anoxsyn 442, an aliphatic sulfide synergist, is particularly effective in crosslinked PE and EVA wire and cable.
Product line also includes high-purity grades of magnesium hydroxide and an ATO replacment synergist
Synergist Express functionality includes web-based timesheet recording, purchasing, job costing, invoicing and expenses, converting the information into a range of reports to give a complete real-time overview of the business.
a heavy exposure to an insecticidal synergist may make a person vulnerable to a variety of toxic insults that would normally be easily tolerated.
Animals were subjected to sham surgeries (Con) or functionally overloaded by bilateral synergist ablation of the gastrocnemius muscle for 3-days (OV).
Civil rights activist Rosa Parks becomes a synergist, guest-starring on ``Touched by an Angel'' (8 p.
Pyrethroid-based products often contain a synergist to increase their potency.