barium Chem.
(ˈbɛərɪəm)
Rarely (and obs.) baryum.
[f. bar-yta, -ytes + -ium; cf. soda, sodium. Davy purposely discarded the second syllable of baryta, as in his proposed alumium from alumina, and magnium from magnesia.]
a. A white metallic element, not found native, but as the basis of the alkaline earth baryta. First separated by Sir H. Davy in 1808.
| 1808 Sir H. Davy in Phil. Trans. XCVIII. 346, I shall venture to denominate the metals from the alkaline earths, barium, strontium, calcium, and magnium. 1819 [See baria]. 1873 Watts Fownes' Chem. 357 Barium occurs as sulphate and carbonate, forming the veinstone in many lead mines. |
| attrib. 1869 Roscoe Chem 221 Barium compounds occur somewhat more widely dispersed than those of strontium. |
b. Special comb.
barium meal, a mixture containing barium sulphate, a white compound that is opaque to X-rays, used in radiological examination of the alimentary tract. So also
barium enema,
barium swallow.
| 1913 Lancet 31 May 1529/2 Dr. J. Delpratt Harris gave a demonstration of a Barium Meal in a case of Gastroenterostomy. 1930 D. A. Rhinehart Roentgenographic Technique xviii. 346 Postero-anterior views of the colon filled with a barium enema. 1940 Med. Ann. 507 A patient..was submitted..for a barium enema examination of the colon. 1946 Brit. Jrnl. Radiology Mar. 114/2 On examination with a barium swallow and meal it was seen that there was..dilatation..of the œsophagus. 1962 Lancet 13 Jan. 67/1 Barium-swallow examinations may fail to demonstrate œsophageal varices. 1966 Listener 24 Feb. 273/1 They performed all sorts of tests on me with barium meals. |