Early Noldorin
u(r)vrog
adjective. horseless
brog
noun. horse
There are more words but they are from Tolkien's earlier conceptional periods. Tolkien likely changed these words as he evolved the aesthetics and completeness of the languages. You may even find languages that Tolkien later rejected. Do not mix words from different time periods unless you are familiar with the phonetic developments.
u(r)vrog
adjective. horseless
brog
noun. horse
Below: Tolkien's Late Period (1950–1973). These are from Tolkien's late conceptual period — his most settled forms of the languages. Prefer these over the earlier ones above when composing new text.
An example negative adjective in Early Noldorin Word-lists of the 1920s that was a combination of the privative prefix ᴱN. ur- and ᴱN. brog “land”; it replaced a deleted form ᴱN. o(r)vrog (PE13/156).