Partners / Elasticsearch

Fix search relevance at the source

Bitext adds a multilingual linguistic layer before Elasticsearch, helping search, semantic search and RAG teams work with cleaner normalized text before indexing.

Instead of relying only on stemming, dictionaries or analyzer tuning, Bitext prepares text with linguistic signals such as lemmatization, decompounding, language-aware segmentation and entity extraction before it reaches the search layer.

Search relevance
Semantic search
RAG preparation
Multilingual indexing
Decompounding

Partner ecosystem

Bitext + Elasticsearch

Bitext complements Elasticsearch by preparing multilingual text before indexing. The result is cleaner linguistic evidence for lexical search, semantic search, hybrid retrieval and RAG workflows.

Bitext

+
Elastic

What we offer

A linguistic normalization layer for Elasticsearch

Bitext improves relevance by enhancing linguistic normalization before indexing — especially lemmatization, decompounding and multilingual consistency. The goal is to reduce query complexity, improve matching and strengthen retrieval quality.

Before indexing
normalize language

After retrieval
reduce noise

Bitext plugin for Elasticsearch

Designed for teams building search, semantic search and RAG

Bitext is designed for teams that need better normalization, more reliable matching and stronger multilingual consistency before content reaches Elasticsearch.

Better normalization

Normalize words with linguistic analysis rather than relying only on approximate stemming behavior.

Reliable matching

Reduce false positives and false negatives caused by weak or inconsistent linguistic analysis.

Multilingual consistency

Improve behavior across English, German, French, Spanish and other multilingual search collections.

Stronger RAG input

Prepare cleaner evidence before chunking, indexing, retrieval and grounding.

Stemming vs lemmatization

Elastic’s default English analyzer can collapse terms that should remain distinct

By default, Elastic’s English analyzer uses the Porter stemmer. Because it is rule-based, it can collapse terms too aggressively, causing false positives and loss of meaning. Bitext lemmatization preserves more linguistic meaning.

InputDefault Porter stemmerBitext lemmatization
Apple / applesApple → appl
apples → appl
Apple → Apple
apples → apple
United / unitUnited → unit
united → unit
unit → unit
United → United
united → unite
unit → unit
useful / useduseful → us
used → us
useful → useful
used → use

In practice, this can lead to false matches and loss of precision, while proper lemmatization preserves meaning and improves search relevance.

The problem today

Lucene-based stemming and decompounding are useful, but not always enough

Elasticsearch works extremely well for general-purpose search, but multilingual and semantic use cases often expose limitations in stemming, tokenization and compound-word handling.

Stemming is used instead of true lemmatization
Compound-heavy languages require extra dictionary work and tuning
Tokenization and splitting behavior is not always consistent across languages and domains
These limitations affect search relevance, semantic retrieval and RAG grounding

Elastic compound-word article

Examples

These issues are not theoretical

Real Elasticsearch users report stemming and decompounding issues in production-like multilingual environments.

Example 1 / French stemming

“Servier” matching “Service”

A user reports that stemming creates false positives in French, including the company name “Servier” matching “Service”.

View discussion →

Example 2 / German decompounding

Inconsistent decompounding behavior

Users also report inconsistent decompounding behavior even when using Elastic’s recommended filters and configuration options.

View issue →

Example 3 / Compound words

Meaning hidden inside compounds

Elastic itself highlights that compound words create search challenges because meaningful components can be hidden inside longer terms.

Read Elastic article →

In other words: stemming and decompounding are useful, but for multilingual search and RAG they can still leave precision, normalization and consistency gaps.

How Bitext solves it

Documents arrive normalized and ready for higher-quality retrieval

Bitext adds a linguistic layer before indexing, so Elasticsearch receives cleaner normalized text and stronger multilingual metadata.

True lemmatization

Use linguistic lemmatization instead of stemming approximations.

Robust decompounding

Improve compound handling, especially for German and other compound-heavy languages.

Multilingual consistency

Improve consistency across English, German, French, Spanish and other languages.

Higher-quality RAG input

Give semantic search and RAG pipelines cleaner evidence before retrieval and grounding.

How it fits

Bitext enriches text before Elasticsearch indexes it

Raw documents go through Bitext linguistic enrichment first. Elasticsearch then indexes cleaner normalized text, language-aware metadata and structured linguistic fields.

01 / Input

Raw content

Documents, records, product data, support tickets, knowledge base content and multilingual text collections.

02 / Linguistic layer

Bitext NLP

Language ID, segmentation, lemmatization, decompounding, POS, entities, phrases and other multilingual linguistic signals.

03 / Search layer

Elasticsearch

Indexes normalized text and linguistic fields for search, hybrid retrieval, semantic search, filtering and ranking.

04 / Applications

AI systems

Enterprise search, AI search, RAG, knowledge workflows, document intelligence and customer-facing applications.

Seamless integration

Normalized indexing and querying without changing application logic

Bitext integrates advanced word segmentation, lemmatization and decompounding into Elasticsearch-style indexing workflows through custom analyzers and token filters.

This enables normalized indexing and querying while preserving the application experience on top of Elasticsearch.

Higher relevance across multilingual collections
Improved recall for compound-heavy languages
No changes required in application logic

Bitext multilingual NLP platform

Beyond Elasticsearch: a full multilingual NLP platform

Bitext provides a full multilingual NLP SDK to power search, AI and structured data extraction across large document collections.

640k

words / sec

High-speed processing on an 8-core CPU.

50MB

disk footprint

Lightweight per-language footprint.

200MB

RAM

Designed for local and enterprise deployment scenarios.

70+

languages

Broad multilingual NLP coverage.

Core capabilities

Language ID, sentence segmentation, lemmatization, word segmentation, decompounding, agglutination, POS tagging, phrase structure tagging, entity extraction and concept extraction.

Supported environments

Linux, macOS, Windows, ARM and x64 environments, with local/on-premises or cloud deployment depending on customer architecture.

AI and search workflows

Semantic search, RAG, entity and concept extraction, vector search, graph creation, compliance workflows and document intelligence.

Use cases

Where Bitext improves Elasticsearch workflows

Bitext is useful when search quality depends on multilingual normalization, better lexical evidence and more reliable retrieval input.

Semantic search and RAG

More grounding and precision, less noise and fewer hallucinations from poor retrieval evidence.

Entity and concept extraction

Fast multilingual enrichment for vector search, graph workflows and compliance-oriented search systems.

Graph RAG

Structured linguistic signals to accelerate knowledge graph creation from unstructured text.

Get started

Evaluate Bitext for your Elasticsearch pipeline

If you are building multilingual search, semantic retrieval or RAG pipelines on Elasticsearch, Bitext can help improve relevance, reduce noise and strengthen linguistic consistency.

MADRID, SPAIN

Camino de las Huertas, 20, 28223 Pozuelo
Madrid, Spain

SAN FRANCISCO, USA

541 Jefferson Ave Ste 100, Redwood City
CA 94063, USA