Loosely, a quasiparticle corresponding to topological twists or kinks in a spin space. Technically, a skyrmion is a soliton Eric Weisstein's World of Math with spin and statistics different from those of the underlying fields in a nonlinear field theory.
References
Ladbury, R. "In a Two-Dimensional Electron System, the Skyrmion's the Limit." Phys. Today 48, 19-21, 1995.
