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 sixth row, labeled "Unknown" shows some First-Class Mail that cannot be identified with any of the aforementioned four sectors.
Cognitive training has demonstrable effects on performance, on views of self, and on brain function—but the results are very specific to the skills that are trained, and it is as yet entirely unknown whether there is any effect on when or whether an individual develops Alzheimer disease.
Koestler argued from circumstance, asserting that it is unclear where all the eastern European Jews came from, that the fate of the Khazars is unknown, and that the solution to both problems is the same.
Preliminary data show that the number of unknown CDSs (ORFs encoding proteins without sequence-similar matches) will be less than 170 after data on the Salmonella typhimurium genome is included (M.H.S.
Although its function is unknown, one possibility is that it serves as a protein interaction domain.