Liquid crystal disclinations are topological defects classified by winding number s = ±½, ±1, ±3/2, ...
The director field n(x,y) = (cos θ, sin θ) winds by 2πs around each defect core. ±½ defects can annihilate (total charge=0), while ±1 defects are energetically costly but topologically stable under certain boundary conditions. Coarsening: after a quench, defects diffuse and annihilate pairwise. The number of defects decays as N(t) ~ t⁻¹ (2D XY model universality). Colors encode director angle θ.