NLP & Language · intermediate · concept 134 of 311 · Updated Nov 4, 2026
Semantic Search
Semantic search finds results by meaning instead of matching exact words, so a question can find a page that answers it in different language. It compares embeddings of the query and the documents. It is the retrieval layer in most RAG systems, and it misses exact names and codes that keyword search catches, which is why the two are often combined.
Key terms
EmbeddingsCosine similarityVector searchRetrievalQuery intent
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Site search, support knowledge bases, RAG systems, product discovery
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