mandelbug definition: Noun (plural mandelbugs) 1. (computing) A software bug whose behaviour appears to be chaotic. ...
The bloodiest single day of battle was Antietam (26,134 casualties). The bloodiest battle, however - which lasted three days - was Gettysburg (51,112 casualties). July 21, 1861.
Fought on September 17, 1862, Antietam was the bloodiest single-day battle in American history with over 23,000 casualties (men listed as killed, wounded, captured or missing) in roughly 12 hours. The battle ended the Confederate invasion of Maryland in 1862 and resulted in a Union victory.