Fortified foods contain vitamin D in the form of either D2 or, more commonly, D3, which is the type produced by human skin exposed to sunlight. Salmon, tuna, swordfish and mackerel are examples of fish whose flesh contains vitamin D, notes the NIH Office of Dietary Supplements.
Definition of Wassermann test. : a test for the detection of syphilis using the Wassermann reaction âcalled also Wassermann.
hertz. A unit used to measure the frequency of vibrations and waves. One hertz is equal to one cycle per second.Radio waves are usually measured in megahertz, or millions of hertz.ertz. n. pl. hertz Abbr. Hz. A unit of frequency equal to one cycle per second. See Table at measurement.