nearest

Definition

As in nearest neighbour: the stored point closest to a query under some distance metric. Treating proximity in embedding space as a proxy for semantic similarity is what underpins vector search and retrieval-augmented generation. Note the split between exact search, which guarantees the true closest point, and approximate search, which trades a little recall for orders-of-magnitude speedup.

Explainers using this term

• Build Your Own Vector DB — From Brute Force to HNSWEfficient and robust approximate nearest neighbor search using Hierarchical Navigable Small World graphs
• Hashing and Nearest-Neighbor Search — The Groundwork Under Vector SearchEfficient and robust approximate nearest neighbor search using Hierarchical Navigable Small World graphs
• Graph Algorithms from Scratch — Shortest Paths and Where They LeadEfficient and robust approximate nearest neighbor search using Hierarchical Navigable Small World graphs