This sounds for all the world like you're pronouncing it CR -- craipe. Is that right?
I guess this word has roots in the Old Norse 'Knappr'.
Yes, you're both right. In the Ulster dialect, words like cnaipe and cnoc (hill) and cnámh (bone) are pronounced craipe, croc and crámh. In the south they still pronounce them with an n. And this word does derive from knappr, a Viking word. The Irish took a small but important group of words from Old Norse. Most of these were to do with boats and sailing (bád = boat, seol = sail, cíle = keel) and with commerce (scilling = shilling, pingin = penny, margadh = market). This word cnaipe is one of the few Viking words in Irish which doesn't belong to these two categories.