carbuncle

nouns

deep-red cabochon garnet cut without facets

carbuncle

is a type of (narrower)

any of a group of hard glassy minerals (silicates of various metals) used as gemstones and as an abrasive

an infection larger than a boil and with several openings for discharge of pus

carbuncle

is derived from

is a type of (narrower)

an infection with staphylococcus bacteria; usually marked by abscess formation