unk-unk
n.— «Many unknowns are evident at the beginning, and may be called “known unknowns.” These are identified early as potential problem areas and are therefore singled out for examination and resolution.…However, many other problem areas are only identified later when they are discovered during system development. These unanticipated problems are often identified as “unknown unknowns” are “unk-unks” to distinguish them from the group of “known unknowns” that were recognized at the outset and dealt with.» —by Alexander Kossiakoff Systems Engineering Nov. 15, 2002. (source: Double-Tongued Dictionary)
Further reading
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Have you ever googled your own name and found someone else who goes by the very same moniker? There’s a word for that: googleganger. Plus, the language of hobbyists and enthusiasts: If you’re a beekeeper, perhaps you call yourself a...