A dark and ominous cloud that appears to indicate a coming storm.(noun)
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Use "stormcloud" in a sentence
"But today's stormcloud of hysteria is a poor prelude to what could emerge from this, not a sensible attempt to redefine journalistic ethics but a cack-handed attempt to restructure an industry."
"Just his herding-dog slink (and he has a most wonderful herding-dog slink, when he wants it) which makes him look like a drifting stormcloud intent on mayhem."
"I eat a mouldy mushroom and it blooms a stormcloud on my belly."