kenyoudaoicibaDictYouDict[ken 词源字典]
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[ken etymology, ken origin, 英语词源]
can (v.1)youdaoicibaDictYouDict
Old English 1st & 3rd person singular present indicative of cunnan "know, have power to, be able," (also "to have carnal knowledge"), from Proto-Germanic *kunnan "to be mentally able, to have learned" (cognates: Old Norse kenna "to know, make known," Old Frisian kanna "to recognize, admit," German kennen "to know," Gothic kannjan "to make known"), from PIE root *gno- (see know).

Absorbing the third sense of "to know," that of "to know how to do something" (in addition to "to know as a fact" and "to be acquainted with" something or someone). An Old English preterite-present verb, its original past participle, couth, survived only in its negation (see uncouth), but see also could. The present participle has spun off as cunning.
kenning (n.)youdaoicibaDictYouDict
Old English cenning "procreation; declaration in court," present participle of ken (v.). From early 14c. in senses "sign, token; teaching, instruction;" c. 1400 as "mental cognition." From 1871 as "periphrastic expression in early Germanic poetry;" in this sense it probably is from a modern learned use of Old Norse cognate verb kenna "to know, to recognize, to feel or perceive; to call, to name (in a formal poetic metaphor)."
In the whole poem of Beowulf there are scarcely half a dozen of them [similes], and these of the simplest character, such as comparing a ship to a bird. Indeed, such a simple comparison as this is almost equivalent to the more usual "kenning" (as it is called in Icelandic), such as "brimfugol," where, instead of comparing the ship to a bird, the poet simply calls it a sea-bird, preferring the direct assertion to the indirect comparison. [Henry Sweet, "Sketches of the History of Anglo-Saxon Poetry," London, 1871]
OuijayoudaoicibaDictYouDict
1891, a trademark name (originally by Kennard Novelty Co., Baltimore, Md.), compounded from French oui + German ja, both meaning "yes."
kenspeckleyoudaoicibaDictYouDict
"Easily recognizable; conspicuous", Mid 16th century: of Scandinavian origin, probably based on Old Norse kenna 'know, perceive' and spak-, spek- 'wise or wisdom'.