Semantic Density refers to the concentration of meaningful, context-rich information within a given span of text, typically measured per token or per paragraph. High semantic density improves vector embedding quality, enhances retrievability by LLMs, and reduces dilution in content chunks.

Why It Matters in AI SEO:

• Dense content yields more precise vector embeddings for semantic search and LLM citation.

• Low-density content introduces noise, weakens retrieval relevance, and inflates token budgets.

• Optimizing for semantic density helps content perform better in zero-click AI surfaces and knowledge retrieval.