Also found in: Dictionary, Thesaurus, Medical, Wikipedia.


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.

Mentioned in ?
References in periodicals archive ?
The utility of camptothecin as a synergist of Bacillus thuringiensis var.
13% Table 6--Effect of Synergist on the Development and Permeability of 15% Mesotrione Dispersible Oil Suspension Synergist mass Distribution Infiltration fraction (%) diameter (mm) time (S) BH-75 1 47 124 2 82 84 3 123 66 6300 1 67 108 2 136 72 3 210 48 blank 0 20 -- Table 7--Thermal Stability of 15% Mesotrione Dispersible Oil Suspensions Active ingredients of Suspending rate of mesotrione mesotrione number Thermal After heat Before Thermal Relative storage storage thermal storage decomposition (%) (%) storage (%) rate (%) (%) 1 15.
Specialist chemicals company Albemarle Corporation (NYSE:ALB) said on Tuesday that it has entered into a collaboration agreement to innovative new methods to increase 3-D visualization of flame retardant and synergist components using element specific X-ray tomography.
Taking into account the synergist and the unidentified ingredients, the synthetic pyrethroids sprayed in the US are not like misting our streets with gentle flower petals.
Pyrethroid-based products often contain a synergist to increase their potency.
Thus, any indication that it was being tested as a toxicant or synergist for a toxicant would be considered sensitive by interested industry and government representatives" And then there was the lab's own interest: Deet had originally been synthesized by the USDA, and the Gainesville lab had field-tested it; over the years, the insect repellent had become a lab staple.
The ability to chelate trace metals also allows citric acid to serve effectively as an antioxidant synergist in fat-containing foods and also in fats and oils when trace quantities are added during the refining process.
AM3D is pleased to partner with Cornet Technology as both companies have the same approach to providing the latest technology and we see this agreement as a synergist way of combining our areas of expertise to effectively enhance customers' ability to perform," said Sven Vestergaard, Senior Vice President, AM3D A/S.
Myclobutanil is a pesticide that is not authorized for use in cannabis cultivation, while piperonyl butoxide is a synergist that is a substance that is combined with pesticides to increase their effectiveness.
In set 1, mites were treated with a miticide and synergist mixture, and in set 2, mites were treated with the miticide alone.
Rio Tinto, our supplier, confirms after recent research that zinc borate is a unique multifunctional fire retardant synergist that enhances effectiveness of existing fire retardant systems significantly by reducing fumes and smoke, as well as suppressing afterglow.