<unk>  (or geometric growth) occurs when the growth rate of a mathematical function is proportional to the function's current value. Such growth is said to follow an<unk>  law; the simple-exponential growth model is known as the Malthusian growth model. For any<unk> ly growing quantity, the larger the quantity gets, the faster it grows. An alternative saying is 'The rate of growth is proportional to the state of growth'. The relationship between the size of the dependent variable and its rate of growth is governed by a strict law of the simplest kind: direct proportion. It is proved in calculus that this law requires that the quantity is given by the<unk>  function, if we use the correct time scale. This explains the name.
Exponential growth
Growth inhibition
Drug resistance
Antibiotic resistance
Fermentation 
Cytopathic effect
Symbiosis
Heterolysis