1. To find out where someone or something is or who or what anyone or something was; such as, to trace a wounded buffalo; tracing a missing child.
2. To follow or to show the course or series of developments of something, or be able to be followed back in time or to a source; for example, to determine the successive stages in the development or progress of someone or something; tracing the life cycle of an ant colony; traced the history of a family ancestry.
3. To copy writing, a design, or drawing by putting translucent paper on top of it and drawing the visible outlines on that paper.
4. To locate or to discover something by searching or researching available evidence; such as, to trace the cause of a disease or a mental illness.
5. To locate origins or to be able to locate the linguistic features of words back to their beginnings: "Scholars can determine the historical origins of English words by tracing them to their Germanic, French, and Latin or Greek origins."