cephalosporin

cephalosporin /ceph·a·lo·spo·rin/ (sef?ah-lo-spor´in) any of a group of broad-spectrum, penicillinase-resistant antibiotics from Acremonium, related to the penicillins in both structure and mode of action. Those used medicinally are semisynthetic derivatives of the natural antibiotic cephalosporin C. First-generation cephalosporins have a broad range of activity against gram-positive organisms and a narrow range of activity against gram-negative organisms; second-, third-, and fourth generation agents are progressively more active against gram-negative organisms and less active against gram-positive organisms.

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ceph·a·lo·spo·rin (sf--l-spôrn)

n.

Any of various broad-spectrum antibiotics, closely related to the penicillins, that were originally derived from the fungus Cephalosporium acremonium and are used to treat bacterial infections.