What is the meaning of Empiricism?

Medicine as practised by an empiric, founded on mere experience, without the aid of science or a knowledge of principles; folk medicine, quackery.

A doctrine which holds that the only or, at least, the most reliable source of human knowledge is experience, especially perception by means of the physical senses. (Often contrasted with rationalism.)

A pursuit of knowledge purely through experience, especially by means of observation and sometimes by experimentation.

used to describe research based on methodology shaped from empirical philosophy (see above), e.g. surveys, statistics, etc.

Source: wiktionary.org