Meanings
gram-positive1
alternative Gram-positive
- not comparablebacteriologyThat is stained violet by Gram's method
Gram-positive2
alternative gram-positive
- not comparablebacteriologyThat stains dark blue or violet after Gram staining, due to large quantities of peptidoglycan in the cell wall.
Note that L.^([Listeria]) monocytogenes is one of the few Gram-positive bacteria against which vancomycin is not effective — hence the need for ampicillin.
2007, Alan R. Hauser, Antibiotic Basics for Clinicians: Choosing the Right Antibacterial Agent, page 2012 more examples
Generally, ionophore antibiotics are highly effective against Gram-positive bacteria but exhibit little or no activity against Gram-negative bacteria (Chen and Wolin, 1979; Watanabe et al., 1981).
1997, T. G. Nagaraja, C. J. Newbold, C. J. Van Nevel, D. I. Demeyer, “13: Manipulation of ruminal fermentation”, in P. N. Hobson, C. S. Stewart, editors, The Rumen Microbial Ecosystem, 2nd edition, page 545The majority of Gram-positive (82%) and Gram-negative (64%) genera carry either ribosomal protection genes alone or in combination with efflux/enzymatic genes as illustrated in Table 7.2.
2011, Patricia L. Keen, Mark H. M. M. Montforts, Antimicrobial Resistance in the Environment, page 108
Synonyms & antonyms
adjective(of bacteria) being or relating to a bacterium that retains the violet stain used in Gram's method
Synonym sets from Open English WordNet, CC BY 4.0.
Origin
gram-positive · adjective
From Gram (“a surname”) + positive, after Danish bacteriologist Hans Christian Gram, who invented the Gram staining method.
Full word history & related roots →Gram-positive · adjective
From Gram (“a surname”) + positive, after Danish bacteriologist Hans Christian Gram, who invented the Gram staining method.
Full word history & related roots →Translations
Catalan gramnpositiu
- gramnpositiustained violet by Gram's method
German grampositiv
- grampositivstained violet by Gram's method
Italian gram-positivo
- gram-positivostained violet by Gram's method
Cite this entry
gram-positive. (n.d.). In WatkinsX Dictionary. Retrieved November 3, 2026, from https://dictionary.watkinsx.com/word/gram-positive
“gram-positive.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/gram-positive. Accessed November 3, 2026.
WatkinsX Dictionary, s.v. “gram-positive,” accessed November 3, 2026, https://dictionary.watkinsx.com/word/gram-positive.
Source: gram-positive on Wiktionary, CC BY-SA 4.0.