v. [UN-2 5, 7.] trans. To deprive of the function of a siphon. Hence Unsiphoned ppl. a.
1878. J. A. Russell, Sanitary Houses, 19. Traps may be unsiphoned by a body of water coming down the soil pipe,… making suction behind it.
1884. E. F. Willoughby, Hygiene, v. 194. This simple … preventative of unsyphoning is … little appreciated.
1894. Times, 20 Feb., 3/6. The unsyphoned traps … of the waterclosets.
