Early Noldorin
cuil
noun. life
cuilvorn
noun. lifetime
cuif
adjective. alive
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!
A word appearing as ᴱN. {cuilborn >>} cuilvorn “lifetime”, a combination of cuil “life” and born “age” (PE13/141). In the Gnomish Lexicon of the 1910s it was G. cuilborn “lifetime” with the same elements (GL/27).
Neo-Sindarin: Since [N.] cuil “life” appears in Tolkien’s later writing, I’d retain ᴺS. cuilvorn “lifetime” for purposes of Neo-Sindarin, and assume the second element was based on the root ᴹ√BOR(ON) “endure”, hence = “✱life’s endurance”.