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Showing results for louse up. Search instead for louse+up.
Synonyms

louse up

Idioms  
  1. Spoil, ruin, bungle. For example, The bad weather loused up our plans, or Your change of mind really loused me up. This slangy expression originated in World War I, when infestation with lice was the common lot of soldiers in the trenches; its figurative use dates from the 1930s.