Words similar to unknown

Example sentences for: unknown

How can you use “unknown” in a sentence? Here are some example sentences to help you improve your vocabulary:

The cause of the crash remains unknown.
Genes in each cluster grouped by the same profile are labeled using COG's 18 broad functional categories excluding category R (general function) and category S (function unknown).
Despite considerable effort, the precise biochemical mechanisms of its action in DNA repair remain unknown.
They're both familiar figures yet somewhat unknown quantities (Hillary as a candidate, Rudy as anything but mayor).
For some reason unknown to lexicographers the word became popular, and it was but a matter of time before it was shortened to pommy and then pom , both of which were used adjectivally as well.