What does Boxing Day have to do with boxing?
1814, "cross," from Latin crux "cross" (see cross (n.)). Figurative use for "a central difficulty," is older, from 1718; perhaps from Latin crux interpretum "a point in a text that is impossible to interpret," in which the literal sense is something like "crossroads of interpreters." Extended sense of "central point" is from 1888.
crux (krŭks, kruks)
n. pl. crux·es or cru·ces (krōō'sēz)
A cross or a crosslike structure.
constellation lying at about 12 hours 30 minutes right ascension (the coordinate on the celestial sphere analogous to longitude on the Earth) and 60 south declination (angular distance south of the celestial equator), now visible only from south of about 30 north latitude (i.e., the latitude of North Africa and Florida). It appears on the flags of Australia, New Zealand, and Samoa (formerly Western Samoa)
city, seat (1852) of Dona Ana county, southern New Mexico, U.S. It lies along the Rio Grande 38 miles (61 km) northwest of El Paso, Texas. It was founded in 1848 at the end of the Mexican-American War. There are many theories surrounding the naming of the town, but none of these legends has ever been verified. A popular account suggests that crude wooden crosses were erected to mark the graves of soldiers and travelers who had died in the area, whence the name Las Cruces (Spanish: "The Crosses"). Cotton and pecans are grown in the area, which is irrigated by Elephant Butte Dam. New Mexico State University (1888) is based in Las Cruces. White Sands Missile Range and White Sands National Monument are to the northeast. Historic Mesilla (briefly the Confederate capital of the Arizona Territory) and the Indian community of Tortugas are nearby. At the end of the 1990s, Las Cruces was one of the fastest-growing cities in the western United States. Inc. 1907. Pop. (2000) city, 74,267; Las Cruces MSA, 174,682; (2007 est.) 89,722; Las Cruces MSA, 198,791.