Lack of familiarity; ignorance or inexperience.(noun)
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Use "unfamiliarity" in a sentence
"But it reveals a certain unfamiliarity with the details of District life:"
"It may well be that the perception of difficulty here merely reflects unfamiliarity, which is likely true of quite a few of the features often cited as leading to difficulty."
"He cheerily called his unfamiliarity with sports "my disgrace" when questioned on the subject by reporters at the weekend."