penicillus
/ˌpɛnɪˈsɪləs/noun
1 Anatomy. A tuft of small blood vessels, (in later use) specifically of arterioles in the spleen.
2 Mycology and Botany. A structure resembling a paintbrush; specifically the conidium-producing body of a fungus of the genus Penicillium and related genera.
Origin
Late 16th century (in an earlier sense). From classical Latin pēnicillus pencil.