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!

Qenya 

morion

masculine name. the Dark One

Another name for Melko in the poem Fíriel’s Song from the 1930s (LR/72), possibly a combination of the stem form mori- of more “dark” and some variation of the agental suffix -ndo.

Conceptual Development: This name also appeared in the Qenya Lexicon from the 1910s, where it was glossed “Son of the Dark” (QL/62), a combination of the root ᴱ√MORO “dark” and some form of yondo “male descendant”.

toi aina, mána, meldielto - enga morion: talantie

they are holy, blessed, and beloved - save the dark one: he is fallen

lóna

adjective. dark