unknowns
un-knowns
noun
Unidentified or unrecognised people, things, or factors that are not yet understood.
"The team faced many unknowns before the expedition."
Thesaurus
Synonyms: unsuspected, terra incognita, unknown region, anon., anonymous, unnamed, unidentified, nameless, unfamiliar, strange, unsung, inglorious
Antonyms: acquaintance, friend, known