N bubble; cloud, bubble, foam, froth, head, spume, lather, suds, spray, surf, yeast, barm, spindrift, cloud, vapor, fog, mist, haze, steam, geyser, scud, messenger, rack, nimbus, cumulus, woolpack, cirrus, stratus, cirrostratus, cumulostratus, cirrocumulus, mackerel sky, mare's tale, dirty sky, curl cloud, frost smoke, thunderhead, nephelognosy, nephograph, nephology, effervescence, fermentation, bubbling, nebula, cloudliness, nebulosity, bubbling, frothy, nappy, effervescent, sparkling, mousseux, frothy, up, cloudy, thunderheaded, vaporous, nebulous, overcast, the lowring element scowls o'er the darkened lands.

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