Modifying Synonyms and Stopwords

To improve relevance, it is helpful for a search application to understand how one word might be used for another. By maintaining a list of synonyms, an index can ensure that a query using one term will return data using another term which has been predefined as a synonym.

Stop words are words or strings that should be ignored either while creating the index or processing the user's query.  As explained earlier, stopwords are usually indexed in modern search applications, but may be omitted from most user searches.  LucidWorks Enterprise includes a default list of stopwords that can be used, or the list can be modified locally. 

To add synonyms to the list, click *Add*. A blank line appears in the list. Type a comma-separated list of at least two synonyms. You do not need to click *Add* again: the list accepts your new entry as soon as you type it.

To edit an entry in the list, move your mouse over the entry and click to select it. Edit the entry as you like.

To delete an entry, click in the entry to select it. Then click *Delete*.

{note:title=Field Configuration for Synonyms}
Fields must be properly configured for synonyms to work properly. If you expect synonyms to operate on a specific field, the settings "Search by Default" and "Enable Query Synonym Expansion" must be enabled or you may experience situations where search results do not include all documents which contain the synonym terms. Unless you give a specific field in your query, LucidWorks Enterprise queries for synonym terms only in those fields which are both enabled for default search and enabled for synonym expansion.

For example, adding a synonym so that "heart attack" is equivalent to "myocardial infarction" will retrieve many more results, but may diminish the quality of the results if the user is a doctor looking for expert documents in his field. After adding synonyms, results should be reviewed to make sure they are having the intended effect on results.{tip}

h2. Editing the List of Stop Words

LucidWorks Enterprise includes a default list of stop words for English. You can edit the list as you like to tailor the use of stop words to the needs of your particular search application.

Click on the arrow by the word *Stopwords* to see a list of stop words.

  !screen-queries-settings-stopwords.1.7.png|border=1!

To add a stop word, click *Add* at the bottom of the list.

To edit an entry in the list, move your mouse over the entry then click to select it. Edit the entry as you like.

To delete an entry, click in the entry to select it. Then click *Delete*.