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ampicillin vs. penicillin

ampicillin

[am-puh-sil-in] / ˌæm pəˈsɪl ɪn /

noun

Pharmacology.

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

penicillin

[pen-uh-sil-in] / ˌpɛn əˈsɪl ɪn /

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.