sulfa drug

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Any of a group of synthetic organic compounds, derived chiefly from sulfanilamide, chemically similar to PABA and capable of inhibiting bacterial growth and activity by interfering with the metabolic processes in bacteria that require PABA.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Antibiotic drugs related to sulphonamide in chemical structure, tending to be bacteriostatic rather than bacteriocidal.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun antibacterial consisting of any of several synthetic organic compounds capable of inhibiting the growth of bacteria that require PABA