Change Summary

Synonym Match Score

synonym_match_score is a per-hit signal returned inside text_match_info for text search results.

It indicates whether a hit matched through a synonym rewrite, and whether synonym prefix matching was involved.

Values

• 0: the hit did not come from a synonym rewrite
• 1: the hit came from a synonym rewrite without synonym prefix matching
• 2: the hit came from a synonym rewrite with synonym_prefix=true

The response also includes:

• synonym_match: boolean for synonym_match_score > 0

Response

Example:

{
  "document": {
    "id": "1",
    "title": "Cool Trousers"
  },
  "text_match": 578730123373578267,
  "text_match_info": {
    "score": "578730123373578267",
    "tokens_matched": 1,
    "fields_matched": 1,
    "best_field_score": "1108091342849",
    "best_field_weight": 1,
    "num_tokens_dropped": 0,
    "typo_prefix_score": 0,
    "synonym_match_score": 1,
    "synonym_match": true
  }
}

Notes

• This signal is metadata only. It does not change the existing ranking behavior by itself.
• synonym_match_score=2 means the hit was produced from the synonym search path with synonym prefix matching enabled.
• A result that could also match directly may still be marked as a synonym match if the winning hit came from the synonym rewrite path.

PR Checklist

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