The order of a reaction is the sum of concentration exponents in the rate law for the reaction. For example, a reaction with rate law d[C]/dt = k[A] 2 [B] would be a third order reaction. Noninteger orders are possible.
ORDER (ORDER OF REACTION; REACTION ORDER)
Meaning of ORDER (ORDER OF REACTION; REACTION ORDER) in English
General chemistry English glossary. Английский глоссарий общей химии. 2012