Thunderhead
Definition 1 of 1

Metaphor
Often used to describe a stormy or conflicted situation

The thunderhead of emotions built up during the argument.
Literary
Commonly employed in poetry to evoke a sense of impending doom

The poet wrote of the dark thunderheads looming over the horizon.
Context
Care should be taken not to confuse the literal and figurative uses

Using 'thunderhead' to describe a slow learner might offend.
Compare with
cloudcumulonimbusstorm
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