Definition of coefficient in US English:

coefficient

noun

• 1Mathematics
A numerical or constant quantity placed before and multiplying the variable in an algebraic expression (e.g. 4 in 4xy).

• ‘Montel also investigated the relation between the coefficients of a polynomial and the location of its zeros in the complex plane.’
• ‘The coefficients on the age variable in the models of organization-environment fit may then approach zero.’
• ‘He extended the applications of the operational method to linear ordinary differential equations with variable coefficients.’
• ‘The problem was to find the roots by adding, subtracting, multiplying, dividing and taking roots of expressions in the coefficients.’
• ‘Hermite had posed the problem of finding the minimal values of quadratic forms in n variables whose coefficients were real.’
• 2Physics
A multiplier or factor that measures some property.

‘the drag coefficient’
‘coefficients of elasticity’
• ‘The shading coefficient is the measure of solar heat gain through the window.’
• ‘The drag coefficient combines several ballistic properties of typical projectiles.’
• ‘It follows that hydrophobic organic compounds have high adsorption coefficients and high bioaccumulation factors.’
• ‘This measure of a material's elasticity is called its coefficient of restitution.’
• ‘Where can I get a list of friction coefficients for different materials?’

Origin

Mid 17th century (in the sense ‘cooperating to produce a result’): from modern Latin coefficient-, from com- ‘together’ + efficient- ‘accomplishing’ (see efficient).

coefficient

/ˌkōəˈfiSHənt//ˌkoʊəˈfɪʃənt/