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lactam

American  
[lak-tam] / ˈlæk tæm /

noun

Chemistry.
  1. any of a group of cyclic amides characterized by the NHCO group, derived from aminocarboxylic acids by the intramolecular elimination of water from the amino and carboxylic groups.


lactam British  
/ ˈlæktæm /

noun

  1. chem any of a group of inner amides, derived from amino acids, having the characteristic group -CONH-

"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

Etymology

Origin of lactam

First recorded in 1880–85; lact(one) + am(ide)

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In their study, Hölzl-Hobmeier and colleagues used axially chiral allenes that have a lactam group attached at C1.

From Nature

The common antibiotic amoxicillin is among the many drugs based on a chemical structure called a lactam.

From Nature

"An evaluation by an allergist for the penicillin and other beta lactam antibiotic allergy is important, is cost-effective and will decrease the use of other more expensive medications," said Dr. Luz Fonacier, head of the allergy section in the division of rheumatology, allergy and immunology at Winthrop-University Hospital in Mineola, N.Y.

From US News

As has been mentioned, chlorophyll a differs from chlorophyll b by having one more oxygen and two less hydrogen atoms in the molecule, and in having one of its nitrogen atoms in the "lactam" arrangement.

From Project Gutenberg