ampicillin

American  

[am-puh-sil-in] / ˌæm pəˈsɪl ɪn /

noun

Pharmacology.

1. a broad-spectrum semisynthetic penicillin, C 16 H 19 N 3 O 4 S, effective against certain susceptible Gram-positive and Gram-negative bacteria.

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ampicillin British  

/ ˌæmpɪˈsɪlɪn /

noun

1. a semisynthetic penicillin used to treat various infections

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ampicillin Scientific  

/ ăm′pĭ-sĭl′ĭn /

1. An antibiotic derived from penicillin that has a broad antibacterial spectrum of action. It is effective against gram-negative and gram-positive bacteria and is used primarily to treat gonorrhea and infections of the respiratory, urinary, and intestinal tracts.

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Etymology

Origin of ampicillin

First recorded in 1965–70; probably am(inobenzyl)p(en)icillin, an alternate chemical name

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Compare meaning

How does ampicillin compare to similar and commonly confused words? Explore the most common comparisons:

• ampicillin vs. penicillin

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Example Sentences

See Examples For:

ampicillin

The researchers examined how resistant each strain was to 16 commonly used antibiotics, including ampicillin combined with sulbactam, meropenem, tetracycline, and vancomycin.

From Science Daily ● Jun. 23, 2026

In some samples, up to 20% of the E. coli were resistant to the frontline antibiotic drug ampicillin.

From Salon ● Jul. 19, 2023

The vector is transferred to a bacterial host that is ampicillin sensitive and those with a disrupted lacZ gene show inability to metabolize X-gal.

From Textbooks ● Jun. 9, 2022

Other drugs that the pathogen has overcome in the past include ampicillin, streptomycin and tetracycline.

From Scientific American ● May 18, 2015

The list includes drugs like penicillin and ampicillin, which are also prescribed for people.

From New York Times ● Jan. 26, 2011

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Related Words

• penicillin

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