ken: [OE] Once a widespread verb throughout English, ken is now restricted largely to Scotland, having taken over the semantic territory elsewhere monopolized by know. In Old English it actually meant not ‘know’ but ‘make known’; it was the causative version of cunnan ‘know’ (ancestor of modern English can). Its relatives in other Germanic languages made the change from ‘make known’ to ‘know’ early – hence German kennen ‘know’, for example In the case of English ken, the impetus is thought to have come from Old Norse kenna ‘know’. The derived noun ken, as in ‘beyond one’s ken’, dates from the 16th century. => can
