What is Haroo!?
1.
An Irish yell of victory or excitment.
After Brigadier General Thomas R. R. Cobb's Irish Regiment of Georgia pushed back Lieutenant Colonel St. Clair Mullholands Irish Brigade, a Captain (3 stripes on the collar) took off his hat and started yelling "Haroo! Haroo!" and the rest of the regiment cheered "Haroo!"
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