Contraction of ne wost; wottest not; knowest not.(phrase)
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Use "nost" in a sentence
"He produced a photocopied page from a czarist-era encyclopedia showing Cossacks listed as second (after Russians) among the Slavic peoples of Russia, and another showing that Cossacks wrote "Kazak" ( "Cossack" in Russian, a word possibly of Turkic origin) under the heading natsional'nost '( "ethnic group") on government forms in the first years after the 1917 revolution."