A word appearing as N. anw in The Etymologies of the 1930s derived from ON. anu under the root ᴹ√ƷAN “male”, where its positioning makes it appear as if it was a cognate of ᴹQ. hanu “a male (man or animal)” (Ety/ƷAN). In the original version of this entry, it was simply glossed “male”, and was initially given as (deleted) {ganw} (EtyAC/ƷAN).
Conceptual Development: Precursors to this word include G. an “person” and G. anos “man” from the Gnomish Lexicon (GL/19).
Neo-Sindarin: Most Neo-Sindarin writers adapt this word as ᴺS. anu to better fit Sindarin’s phonology. In HSD (HSD), Didier Willis suggested (as originally proposed by David Salo) that this word is most likely an adjective, the cognate of adjective ᴹQ. hanwa “male” rather than the noun ᴹQ. hanu “a male (man or animal)”. This is because it is generally believed that final -u (as in ✶ʒanu) vanishes in Noldorin/Sindarin, while the final -wa (as in ✶ʒanwa) would have developed into -u (Noldorin -w). However, I think the evidence of the loss of final -u in Noldorin is ambiguous and in fact N. anw might be a counterexample, especially since the Old Noldorin form was anu; see the entry on how [[s|final [i], [u] generally vanished]] for further discussion.
In any case, I think anu “male” can be used as a both a noun and an adjective for purposes of Neo-Sindarin.
A literal interpretation of the Etymologies would class this word as a noun, but David Salo notes that the punctuation in The Etymologies is not always reliable. Noldorin anw cannot be cognate to the Quenya noun hanu (3anû) because the final -u would drop. It must rather be cognate to the Quenya adjective hanwa (3anwâ) attested under the stem INI, where it is also stated that inw, corresponding to Quenya inya "female", has been remodelled after anw. The combination of these two entries, along with the phonological evidences, clearly indicates that anw is actually an adjective