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general::
Phrase(s): loom up
to appear to rise up [from somewhere]; to take form or definition, usually threatening to some degree. • A great city loomed up in the distance. It looked threatening in the dusky light. • A ghost loomed up, but we paid no attention, since it had to be a joke. • The recession loomed up, and the stock market reacted.
McGrawhill's American Idioms And Phrasal Verbs