Earlier name of Borlach (LR/134). In The Etymologies, it was given as a derivative of ON. Boronmīro (Ety/BOR). The medial [m] developed from [mm] < [n+m], which is why it did not become [v]. This is a distinct etymology of the later name of S. Boromir of Gondor, where the medial [m] was explained by the fact that it was a mixture of Sindarin and Quenya elements.