Main Entry:

ki·net·ics

Pronunciation:

\kə-ˈne-tiks also kī-\

Function:

noun plural but singular or plural in construction

Date:

circa 1859

1 a: a branch of science that deals with the effects of forces upon the motions of material bodies or with changes in a physical or chemical system b: the rate of change in such a system2: the mechanism by which a physical or chemical change is effected