An Etymological Dictionary of the German Language, R (1891)
by Friedrich Kluge, translated by John Francis Davis
rucken
Friedrich Kluge2510788An Etymological Dictionary of the German Language, R — rucken1891John Francis Davis

rucken, vb., ‘to coo’ (of pigeons), allied to MidHG. ruckezen, ‘to coo,’ and rucku, interj., ‘coo!’ (of pigeons); onomat. forms.