Obtund

Latin obtundere ("to dull", "deaden", "deafen"), from ob- + tundere

Full definition of obtund

(transitive, chiefly medicine) To reduce the edge or effects of; to mitigate; to dull.

1900, Martha M. Allen, Alcohol, a Dangerous and Unnecessary Medicine, ,... the use of alcoholic decoctions... which are given as medicines to allay pain, obtund nerve sensibility, to cure the little sufferer of his vital manifestations ...
2008, Jerrold H. Levy, Kenichi A. Tanaka & Eric J. Okun, "Cardial Surgical Pharmacology", in Cardiac Surgery in the Adult, ISBN 0071469133, p. 103,Small doses of opioids are also useful in obtunding airway reflexes ...