Also found in: Acronyms.
rat unitAn obsolete, semi-quantitative unit corresponding to the minimum amount of an oestrogenic substance required to produce characteristic desquamation of vaginal epithelium in ovarectomised rats.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.
The greatest dilution of estrogen that will cause desquamation and cornification of the vaginal epithelium if given to a mature spayed rat in three injections, one every 4 hr.
Medical Dictionary, © 2009 Farlex and Partners