a mark left by the shod or unshod foot, as in earth or sand.
an impression of the sole of a person's foot, especially one taken for purposes of identification.
Informal. the track of a tire, especially on wet pavement.
a unique set of characteristics, actions, etc., that leave a trace and serve as a means of identification: Be careful when you post on social media—your online footprint could harm your reputation. The tumors share the same genetic footprint.
the area affected by an increase in the level of sound or noise, as that generated by an airplane.