logarithm
Pronunciation:
/ˈlɑ.ɡə.ɹɪ.ð(ə)m/noun
Definitions
For a number x, the power to which a given base number must be raised in order to obtain x. Written \log_b x. For example, \log_{10} 1000 = 3 because 10^3 = 1000 and \log_2 16 = 4 because 2^4 = 16.