GO:0036053

A large plasma membrane-lined circular pore that perforates the flattened glomerular endothelium and, unlike those of other fenestrated capillaries, is not spanned by diaphragms; the density and size of glomerular fenestrae account, at least in part, for the high permeability of the glomerular capillary wall to water and small solutes. [GOC:cjm, MP:0011454, PMID:19129259]