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1. the series of images resulting from the refraction of electromagnetic radiation (e.g., light, x-rays) and their arrangement according to frequency or wavelength.
2. range of activity, as of an antibiotic, or of manifestations, as of a disease. adj., adj spec´tral.
absorption spectrum one obtained by passing radiation with a continuous spectrum through a selectively absorbing medium.
broad-spectrum effective against a wide range of microorganisms.
visible spectrum that portion of the range of wavelengths of electromagnetic vibrations (from 770 to 390 nanometers) which is capable of stimulating specialized sense organs and is perceptible as light.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
Widely applicable or effective: a broad-spectrum antibiotic.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.
broad-spectrumadjective Referring to any agent, usually understood to be an antibiotic, which is effective against a wide range of microorganisms.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.
broad-spectrumadjective Referring to any agent, usually understood to be an antibiotic, which is effective against a wide range of microorganisms
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.
broad-spectrumA term most commonly applied to antibiotics implying that the drug is effective over a wide range of organisms. Widely applicable or effective. Prolonged use of broad-spectrum antibiotics, such as AMPICILLIN or the CEPHALOSPORINS, will usually destroy most of the normal organisms of the bowel and these will tend to be replaced by resistant species. It is therefore considered better practice to use narrow-spectrum drugs so long as these are known to be effective against the organism concerned.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005