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conocer (Verb) "to know;" "to become acquainted with"
11th cent. From Latin cognoscere 'id.' From Proto-Italic *ko-gnōske- 'id.' From *ko-, a perfectizing prefix (see co-), and *gnōske- "to get to know." From Proto-Indo-European *ǵnh3-sḱé- 'id.'
Indo-European
Romance
Asturian coñocer, Portuguese conhecer, Galician coñocer, Catalan conèixer, French connaître, Italican conoscere, Aromanian cunoashtiri, Romanian cunoaștere, Sardinian connòschere
Italic
Archaic Latin gnoscier "to get to know"
Celtic
Old Irish adgnin "to recognize," Welsh atnabot 'id.,' Cornish aswonvos "to know"
Germanic
Gothic kunnan, Old High German kunnan, English to know
Albanian
Albanian njoh
Balto-Slavic
Old Church Slavonic znati, Lithuanian žinóti, Old Prussian posinnat, Latvian zinât
Hellenic
Ancient Greek γιγνώσκειν (gignóskein) "to be aware of"
Armenian
Armenian čanač'em "to recognize"
Indo-Iranian
Sanskrit jānā́ti, Young Avestan paitizana- "to acknowledge," žnātar- "knower"
Tocharian
A āknats, B aknātsa

On the basis of Western Romance languages and Sardinian, a Vulgar Latin form may be reconstructed as *connocer. Other languages have inherited the Classical Latin word, preserving the (Istriot cugnussi, Romansh cugnuoscher, Friulian cognoss).

The distinction of conocer "to know" (as in to familiarize oneself) against saber "to know" (experientially), dates back to Vulgar Latin. Possibly preserving the Proto-Italic sense of *ko-gnōske- "to be acquainted with."