REACTANT

Pronunciation (US):

(GB):

 Dictionary entry overview: What does reactant mean? 

• REACTANT (noun)
  The noun REACTANT has 1 sense:

1. a chemical substance that is present at the start of a chemical reaction

  Familiarity information: REACTANT used as a noun is very rare.

 Dictionary entry details 

• REACTANT (noun)

Sense 1

Meaning:

A chemical substance that is present at the start of a chemical reaction

Classified under:

Nouns denoting substances

Hypernyms ("reactant" is a kind of...):

chemical; chemical substance (material produced by or used in a reaction involving changes in atoms or molecules)

Derivation:

react (undergo a chemical reaction; react with another substance under certain conditions)

 Context examples 

A unit for measuring catalytic (e.g. enzymatic) activity, the ability of the compound to accelerate the chemical reaction by providing a lower energy pathway between the reactants and the products.

(Katal, NCI Thesaurus)

Ornithine is one of the key reactants in the urea cycle that is responsible for 80% of the nitrogen excretion in the body.

(Ornithine, NCI Thesaurus)

"Molten" refers to the electrolyte, which is mixed with reactants for iron, carbon or vanadium boride, then heated until the mixture becomes liquid.

(New, high-energy rechargeable batteries, NSF)

A dimensionless value that refers to the molar concentrations of chemical reactants and products under standard conditions.

(K Prime, NCI Thesaurus)

The American College of Rheumatology criteria consists of a variety of measures such as, the number of tender joints, number of swollen joints, patient's assessment of pain, patient's and physician's global assessments of disease activity, patient's assessment of physical function, and laboratory evaluation of an acute-phase reactant.

(American College of Rheumatology Criteria for Improvement in Rheumatoid Arthritis, NCI Thesaurus)

The steps along the pathway each involve a change in the free energy of the products and reactants, and as long as the overall change in free energy is negative, the reaction continues forward, like water flowing down hill to its lowest energy point.

(Glycolysis Pathway, NCI Thesaurus/BIOCARTA)