a rapid increase in number; " the proliferation of nuclear weapons"

growth by the rapid multiplication of parts

a rapid increase in number ( especially a rapid increase in the number of deadly weapons); " the proliferation of nuclear weapons"

Prolification ; increase by frequent and repeated reproduction of any kind.

Proliferation consists in the unexpected and abnormal on- growing or budding out of parts- stems, tubers, flowers, fruits, etc. – Disease in Plants by H. Marshall Ward