PABA noun1 •Para-aminobenzoic acid, a member of the B-complex family of vitamins that can be synthesized by the human body from folic acid, and used primarily as an active ingredient in sunscreen, but also is necessary for some intestinal bacteria.The inhibitory action of PABA on the growth of rickettsiae was first demonstrated experimentally against murine typhus in 1942 by Snyder, Maier, and Anderson. — 1968
