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.
Gettysburg was the bloodiest battle of the Civil War. It is estimated that there were at least 45,000 and possibly as many as 51,000 casualties in the two armies at Gettysburg.