The story
Blend of sparse + consistency.
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: Let mathbf b be a vector and define the support operatorname supp( mathbf b)=i: mathbf bᵢ≠0 where mathbf bᵢ is the ith element of mathbf b. Let ̂mathbf b be an estimator for mathbf b. Then sparsistency is the property that the support of the estimator converges to the true support as the number of samples grows to infinity. Full definition →
Blend of sparse + consistency.
Etymology from Wiktionary, CC BY-SA 4.0.