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penicillin
[ pen-uh-sil-in ]
/ ˌpɛn əˈsɪl ɪn /
See the most commonly confused word associated with ampicillin
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noun Pharmacology.
any of several antibiotics of low toxicity, produced naturally by molds of the genus Penicillium and also semisynthetically, having a bactericidal action on many susceptible Gram-positive or Gram-negative cocci and bacilli, some also being effective against certain spirochetes.
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Origin of penicillin
First recorded in 1925–30; penicill(ium) + -in2
Words nearby penicillin
penholder, -penia, penicil, penicillamine, penicillate, penicillin, penicillium, penile, penillion, peninsula, Peninsular State
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022
How to use penicillin in a sentence
British Dictionary definitions for penicillin
penicillin
/ (ˌpɛnɪˈsɪlɪn) /
noun
any of a group of antibiotics with powerful bactericidal action, used to treat many types of infections, including pneumonia, gonorrhoea, and infections caused by streptococci and staphylococci: originally obtained from the fungus Penicillium, esp P. notatum. Formula: R-C 9 H 11 N 2 O 4 S where R is one of several side chains
Word Origin for penicillin
C20: from penicillium
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for penicillin
penicillin
[ pĕn′ĭ-sĭl′ĭn ]
An antibiotic drug obtained from molds of the genus Penicillium and used to treat or prevent various infections caused by gram-positive bacteria such as streptococcus. Penicillin was the first of a class of antibiotics (whose names end in -icillin) that are derived from it and are active against a broader spectrum of bacteria. See Note at Alexander Fleming.
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Cultural definitions for penicillin
penicillin
An antibiotic that is used to treat infections caused by some kinds of bacteria. Penicillin, which is derived from a common kind of mold that grows on bread and fruit, was the first antibiotic discovered and put into widespread use.
notes for penicillin
Penicillin was first widely used during World War II.
The New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.