obsolete flagellum part true GO:0044460 This term was made obsolete because it was an unnecessary grouping term. Eukaryotic flagella were deemed to be equivalent to cilia and merged, so the only remaining child to this term was 'bacterial-type flagellum part ; GO:0044461'. flagellum part OBSOLETE. Any constituent part of a flagellum, a long whiplike or feathery structure borne either singly or in groups by the motile cells of many bacteria and unicellular eukaryotes and by the motile male gametes of many eukaryotic organisms, which propel the cell through a liquid medium. flagellum component cellular_component