In machine learning and pattern recognition, a feature is an individual measurable property or characteristic of a phenomenon being observed.^[1] Choosing informative, discriminating and independent features is a crucial step for effective algorithms in pattern recognition,classification and regression. Features are usually numeric, but structural features such as strings and graphs are used in syntactic pattern recognition. The concept of “feature” is related to that of explanatory variable used in statistical techniques such as linear regression.

https://en.wikipedia.org/wiki/Feature_(machine_learning)