xi-c baryon

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Either of two subatomic particles in the baryon class, having a charm quark, a neutral or positive charge, masses of 4,834 and 4,826 times that of an electron, and average lifetimes of 3.5 × 10⁻¹³ and 9.8 × 10⁻¹⁴ second, respectively.