I just ran across the marvelous phrase “kenspeckle bop tunes,” and turned to the Concise Oxford, where I found:
kenspeckle /’kɛnˌspɛk(ə)l/ adj. Scottish conspicuous; easily recognizable
—ORIGIN C16: of Scand. origin, prob. based on ON kenna ‘know, perceive’ and spak-, spek- ‘wise or wisdom’
Now, Old Norse spakr ‘wise’ is apparently from the PIE root *spek- ‘observe,’ which is the source of Latin specere ‘to look at’ and speciēs ‘a seeing, sight, form,’ Greek skeptesthai ‘to examine, consider’ and skopos ‘one who watches; object of attention, goal,’ and a great many other words — scroll down to spek- at the American Heritage Dictionary Indo-European Roots Appendix for all the traces it has left in English. And if you scroll to gnō- ‘to know’ you’ll see the even larger number of traces left by that highly productive root, including ken. A nice, unexpected little Indo-European package!