What is the name for the trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock?

Fossil is the name that is used for the trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock.

Explanation:

Fossils are the remaining parts of the organism's body which lives in ancient times and now they are extinct. Extinct means they are no longer the part of our earth or there is no specie of their kind. Fossil is only be found when the dead bodies of animals buried quickly so the chances of their complete decomposition is less and people will get it during digging after long time.