how are they classified?
The domestic cat is regarded as a distinct species, "Felis catus".
Cat
 In 2017, the IUCN Cat Classification Taskforce followed the recommendation of the ICZN in regarding the domestic cat as a distinct species, "Felis catus".
where did the term 9 lives come from It is a myth in many cultures, cats have multiple lives as they exhibit the natural suppleness and swiftness to escape life-threatening situations.
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Cat [SEP] Taxonomy
The scientific name "Felis catus" was proposed by Carl Linnaeus in 1758 for a domestic cat. "Felis catus domesticus" was proposed by Johann Christian Polycarp Erxleben in 1777. "Felis daemon" proposed by Konstantin Alekseevich Satunin in 1904 was a black cat from the Transcaucasus, later identified as a domestic cat. In 2003, the International Commission on Zoological Nomenclature ruled that the domestic cat is a distinct species, namely "Felis catus". In 2007, it was considered a subspecies of the European wildcat, "F. silvestris catus", following results of phylogenetic research. In 2017, the IUCN Cat Classification Taskforce followed the recommendation of the ICZN in regarding the domestic cat as a distinct species, "Felis catus".