genealogist

noun pl. genealogies

1. a chart or recorded history of the descent of a person or family from an ancestor or ancestors
2. the science or study of family descent
3. descent from an ancestor; pedigree; lineage

Origin: ME genelogi < OFr genealogie < LL genealogia < Gr < genea, race, descent (akin to genos: see genus) + -logia, -logy