A preposition attested only in the phrase “on us” in the Lament of Akallabêth, changing through the drafts as nēnum >> nēnu >> nēnud (SD/247, 312). Most authors identify -nud as the prepositional element (AAD/20, LGtAG, NBA/14), perhaps related to Q. nu “under”. If so, it may be a derivative of the Elvish roots √NŪ/UNU “under” or √NDU “down”, with a semantic shift to the meaning “on”.
Noldorin
nud-
verb. to tie, bind
nud-
verb. *to tie
nod-
verb. to tie
A verb glossed “tie” in The Etymologies of the 1930s, appearing as nud- under the root ᴹ√NUT “tie, bind” (Ety/NUT) but as nod- under the entry for the root ᴹ√WŌ, where Tolkien said it coalesced with N. nod- “count” in Exhilic Noldorin (Ety/WŌ). Since [[s|short [u] generally became [o]]] in Sindarin and Noldorin, it seems nud- was an archaic form and the modern form was nod- “to tie”, crowding out nod- “count” which in turn was replaced by other independent verbs like N. gonod- “to count (up)”, though nod “count” survived as an element in compounds (Ety/NOT, WŌ).