Definitions:
indicating the point in space at which a journey, motion, or action starts

indicating the point in time at which a particular process, event, or activity starts

indicating the source or provenance of someone or something

indicating the starting point of a specified range on a scale

indicating the point at which an observer is placed

indicating the raw material out of which something is manufactured

indicating separation or removal

indicating prevention

indicating a cause

indicating a source of knowledge or the basis for one's judgement

indicating a distinction