Synonyms
Synonyms are exclusive to the index table engine, supporting any custom post type and media attachment contents.
Important: Synonyms are only supported by the Index Table search engine. They have no effect when an instance uses the standard (regular) engine. See the Index Table documentation for how to switch an instance to the Index Table engine.
You'll find it under Ajax Search Pro → Synonyms in the WordPress admin menu.
How matching works
Expansion is bidirectional. A synonym group works in every direction — defining car → automobile, vehicle means searching for car, automobile or vehicle will match content containing any of them. You don't need to create separate entries for each direction.
Post/page search bakes synonyms into the index. For regular content, synonyms are applied when the index is built, so changing synonyms requires re-creating the index before the change takes effect (the panel reminds you — see Re-indexing).
Taxonomy term search expands at query time. When searching taxonomy terms (categories, tags, etc.), synonyms are applied live per search, so those don't require a re-index.
Managing synonyms
The Manage panel lists your synonym entries in a table — the Term, its Synonyms (a comma-separated list), and the Language — with Edit and Delete actions per row.
The toolbar across the top lets you:
Search — filter the list by term.
Language filter — show entries for Any language, Default, or a specific language (on multilingual sites).
+ Add New — create a new synonym entry.
Export / Import — back up or restore your synonyms (see Import & export).
Wipe All — delete every synonym (with confirmation).
The list is paginated (10/25/50/100 per page).
Adding or editing a synonym
Click + Add New (or Edit on a row) to open the editor:
Term — the base word or phrase.
Synonyms — the equivalent words. Type each one and press Enter or comma to add it as a chip.
Language — Default, or a specific language on multilingual sites (see Languages).
Click Save. Terms and synonyms are normalized automatically (lowercased, trimmed). Because expansion is bidirectional, you only list the alternatives once — no need to repeat the term inside the synonyms.
Re-indexing
Whenever you add, edit or delete synonyms, the post index becomes stale — the change won't affect post/page results until the index is rebuilt. The panel shows a warning banner when this happens:
"Synonyms were changed — the post index may be stale."
with a link to the Index Table page. Run a new index there to apply your synonym changes. (Taxonomy term searches don't need this, since they expand synonyms at query time.)
Languages
On multilingual sites (e.g. WPML or Polylang), each synonym entry is tied to a language:
Default — applies when no specific language context is set.
A specific language — applies only to searches in that language.
Use the language filter in the toolbar to view and manage entries per language, and set the language in the editor when creating an entry. On single-language sites you can simply leave everything as Default.
Import & export
Export downloads all your synonyms as a JSON file (named with a timestamp), ideal for backups or moving synonyms between sites.
Import uploads a synonyms file (JSON) and adds its rows to your list. After importing, the panel tells you how many rows were imported.
AI Synonym Discovery
Each row (and the table in the Statistics panels) has a Discover button — a sparkle icon — that opens AI-suggested synonyms for that term, grounded in your own content. Click Add on a suggestion to apply it instantly. This is part of the Search AI suite and requires the AI Synonym Discovery feature to be enabled there.
Generate synonyms in bulk (AI)
Rather than discovering synonyms one term at a time, the Generate (AI) button in the toolbar (the sparkle icon) creates synonyms for your most popular indexed keywords in one pass, then lets you review and accept them together.
Requirements: the AI Synonym Discovery feature must be enabled in Search AI, and your Index Table must be built — the candidate keywords are taken from the index.
It works in two steps:
Configure — choose how many top keywords to cover (e.g. top 25, 50 or 100) and the language for the suggestions, then click Generate. Generating for more keywords uses more of your monthly AI token budget.
Review — the suggestions appear grouped by keyword:
Each suggested synonym is a clickable chip; selected ones (highlighted) will be added.
Synonyms that are already in your list are shown greyed out with an "added" badge and are excluded — nothing is duplicated.
Keywords that already have synonyms are still included, so the AI can suggest complementary additions (marked "complements existing").
Click a chip to include or exclude it, then Add selected to apply them all at once.
Accepted synonyms are merged into your list (no duplicates), and — as with any synonym change — the post index is marked stale, so run a re-index afterward (see Re-indexing).
Tips & notes
Switch the instance to the Index Table engine first — synonyms do nothing on the standard engine.
Rebuild the index after changing synonyms so post/page results reflect the change.
One entry, both directions — you don't need reciprocal entries; expansion is bidirectional.
Mine your zero-result searches. Check the Statistics Popular/zero-result phrases and use Discover to turn them into synonyms that start matching.
Seed a fresh site fast. Use Generate (AI) to create synonyms for your top indexed keywords in one go, then review and accept — a quick head start before fine-tuning by hand.
Back up before bulk changes — Export to JSON before a large import or a Wipe All.
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