More from this author. 1  Largest World Cities: 2014. 2  World Urban Areas Population and Density: A 2012 Update. 3  Largest Cities in the World: 2016. 4  Largest 1,000 Cities on Earth: World Urban Areas: 2015 Edition. 5  The Costs of Smart Growth Revisited: A 40 Year Perspective.
Definition of fossil. 1  1 : a remnant, impression, or trace of an organism of past geologic ages that has been preserved in the earth's crust â compare living fossil. 2  2a : a person whose views are outmoded : fogyb : something (such as a theory) that has become rigidly fixed.
Fossils are remains or traces of past organisms that have been preserved by nature. And here's a fun fact: the word 'fossil' is Latin and actually means 'obtained by digging,' which makes sense because they are often buried. Types of Fossils. There are many ways fossils can form, and we'll get to all that in a minute. First, let's discuss the two main ways that fossils can be classified: Body fossils ; and trace fossils ; The remains of a Hadrosaur are an example of a body fossil, or fossils of the actual organism.