Synonym Expansion

What is Synonym Expansion?

Synonym expansion maps a query term to related or equivalent terms. For example: sneakers ↔ trainers, TV ↔ television. Engines can expand one-way (couch → sofa) or two-way (sofa ↔ couch).

How It Works (quick)

• Dictionary-based: Predefined synonym sets.
• Rule-based: Category or context-specific expansions.
• ML-based: Learned embeddings that cluster similar terms.
• Scope: Apply at query time or index time.

Why It Matters in E-commerce

• Vocabulary gap: Shopper vs vendor language alignment.
• Seasonality: “Winter coat” ↔ “parka.”
• Conversion: Reduces zero-results caused by wording mismatches.

Best Practices

• Start with manual synonym lists; grow with query log analysis.
• Apply locale-specific synonyms (US sneakers vs UK trainers).
• Monitor precision drift; avoid over-expansion (e.g., dress ↔ skirt).
• Use weighted synonyms or contextual rules for ambiguous terms.
• Regularly audit and prune low-value expansions.

Summary

Synonym expansion closes the gap between user queries and catalog wording. Done carefully, it reduces zero-results and improves findability.