A noun appearing as ᴱQ. aiko (aiku-) “cliff” in the Qenya Lexicon of the 1910s, apparently a noun variant of ᴱQ. aiqa “steep” appearing nearby (QL/29). Since ᴹQ. aiqa “steep” continued to appear in Tolkien’s later writings (Ety/AYAK), perhaps this word can be salvaged for Neo-Quenya writing as ᴺQ. aico (aicu-).
Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!