[mod. ad. (in Cotgr., 1611) Gr. ἀνεύρυσμα or ἀνευρυσμός dilatation, f. ἀνευρύνειν to widen out, f. ἀνά up, back + εὐρύν-ειν to widen, f. εὐρύ-ς wide. The spelling with y is etymological; but that with i, by form-assoc. with the ending -ism, is more frequent.]
1. Path. A morbid dilatation of an artery, due to disease in the arterial coats, or to a tumor caused by their rupture. Also attrib.
1656. Ridgley, Pract. Physic, 7. New Aneurisms may be cured, but old not.
1728. in Phil. Trans., XXXV. 436. An Aneurysm, without Doubt, is a Tumour arising from some Disorder in an Artery.
1743. trans. Heister’s Surg., 290. A true Aneurism has always a Pulsation.
1836–9. Todd, Cycl. Anat. & Phys., 225/1. After which the ligature is to be carried round it [the artery] by means of a blunt aneurism-needle.
1859. Carpenter, Anim. Phys., v. (1872), 229. Arteries are liable to a peculiar disease termed Aneurism which consists in a thinning-away or rupture of the tough fibrous coat.
1880. Legg, Bile, 92. Aneurysm of the hepatic artery.
2. transf. and fig. An abnormal enlargement.
1880. T. Hodgkin, Italy & Invad., I. I. iv. 23. The Eastern half of the Empire … had suffered the dangerous aneurism of the Gothic settlement south of the Danube.
1881. Tait, in Nature, XXV. 92/1. There is another peculiarity of the Challenger thermometers … viz. that at the lower end of each of the two vertical columns there is an aneurism on the tube.
