A scientist who studies fossils; a paleontologist (archaic or alternate term).
From fossil + -logy (Greek logos 'study') + -ist (Greek -istes 'practitioner'). Combines fossil with the learned suffix structure meaning 'one who studies fossils'.
This term is almost obsolete—nobody uses 'fossilogist' anymore because 'paleontologist' (from Greek paleo 'ancient' + onto 'being') became the standard. But it shows how scientific terminology evolves and gets replaced by better terms!
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