What does diplococcus mean?
Diplococcus is a technical term for a spherical bacterium, or coccus, that characteristically occurs in pairs. During cell division, the two daughter cells remain attached, creating the paired arrangement from which the name derives. Diplococci are important in medicine because some species cause disease; Gram-negative diplococci associated with a specimen may, for example, suggest certain bacterial infections, although identification requires proper testing. The word also has a historical taxonomic use: Diplococcus pneumoniae was the former designation of the bacterium now called Streptococcus pneumoniae. In general writing, diplococcus is uncommon and belongs mainly to microbiology and clinical contexts. Its standard plural is diplococci. The term is easily confused in spelling with diplopia, but the two have unrelated meanings: one concerns paired bacteria, while the other means double vision.
nounA spherical bacterium (coccus) that characteristically occurs in pairs, with daughter cells remaining attached after division.
- Any spherical bacterium that characteristically occurs in pairs as a result of its division pattern.
- A historical taxonomic designation, especially Diplococcus pneumoniae, the former name for the bacterium now classified as Streptococcus pneumoniae.
"The laboratory report identified Gram-negative diplococci in the specimen."
"Microscopic examination of the sputum revealed intracellular diplococci."
"Diplococcus pneumoniae was the organism's former scientific name."
The standard plural is diplococci, written without an apostrophe.
"Microscopic examination revealed Gram-negative diplococci in the specimen."
A diplococcus splits in two but often refuses to say goodbye: the daughter cells remain joined like a bacterial pair.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does diplococcus come from?
Diplococcus was formed in New Latin from Greek diplóos, meaning “double,” and kókkos, meaning “berry,” a term traditionally used for spherical bacterial cells. The “double” element refers to the characteristic pairing of the cells. Diploid and diplopia share the Greek element diplo-, while streptococcus and gonococcus belong to the broader family of words built from kókkos.
Related word forms
How diplococcus is actually used
This is primarily a technical term used in microbiology, clinical medicine, and laboratory reports. It is normally lowercase in its general sense, while the historical taxon Diplococcus pneumoniae is capitalized.
Easily confused with diplococcus
Diplococcus is a paired spherical bacterium, whereas diplopia is double vision.