Bloody Sunday

Proper noun

 * 1)  A 1905 event in St Petersburg in which as many as 4,000 unarmed citizens were killed by state forces.
 * 2)  A 1965 event in Selma, Alabama, where peaceful civil rights protesters were brutally beaten by police.
 * 3)  A 1972 event in Northern Ireland in which 14 civil rights protesters were shot and killed by a British Army regiment.
 * 4)  Any of many similar events; see Bloody Sunday on Wikipedia for a complete list.
 * 1)  Any of many similar events; see Bloody Sunday on Wikipedia for a complete list.