naked virus, nonenveloped virus a virus lacking an outer lipoprotein bilayer. neurotropic virus one that has a predilection for and causes infection in nervous tissues, e.g., the rabies virus. Norwalk virus a calicivirus that is a common agent of epidemics of acute gastroenteritis. oncogenic viruses an epidemiologic class of viruses that are acquired by close contact or injection and cause usually persistent infection; they may induce cell transformation and malignancy.
Define stumbling block: an obstacle to progress; an impediment to belief or understanding : perplexity â stumbling block in a sentence an obstacle to progress; an impediment to belief or understanding : perplexityâ¦
(blÅk) n. 1. a. A solid piece of a hard substance, such as wood, having one or more flat sides. b. Such a piece used as a construction member or as a support. c. Such a piece upon which chopping or cutting is done: a butcher's block. d. Such a piece upon which persons are beheaded.