There are three main reasons to add custom terms to the ATG Search dictionary:
The term is not in the default dictionary, but does appear in your searchable content or in user queries. Examples include product names and industry-specific terms.
You want to add a synonym that does not exist in the default dictionary to an existing dictionary term. These might include product or brand names that are often abbreviated or referred to by acronyms. To do this, add the term to a custom dictionary and then add the synonym. (See also, Why Add Synonyms and Child Terms)
You want to override the default synonyms in the dictionary, either because you do not want to use those default synonyms, or because you want to add synonyms that apply to your content but are not in the default dictionary. To do this, add the term to a custom dictionary and then add synonyms if appropriate. (See also, Why Add Synonyms and Child Terms)
When you are deciding whether you should add a custom term, consider the questions posed in the sections that follow.
Note: Before you add any terms to a dictionary, use Dictionary Inspection to make sure that you are not adding a term that is already in the core dictionary. Adding duplicate terms can cause unpredictable search results for your users, if you have not also specified the appropriate override behavior for the dictionary.
Does the Term Appear in Other Forms
If your term (such as a company name, brand name, or product name) is unlikely to be pluralized or to appear in more than one form, you do not need to add it to a dictionary. Although the term is recorded and reported on as “unknown,” that does not mean that the term is not searchable. A term searched on always matches that exact string in the indexed content, whether or not the term is in a dictionary.
If the term does appear in a plural or other variant form, then you should add it as a custom term. If the term is a single word, specify the part of speech when you add the term; Search can then identify morphological variations such as the plural form or past tense automatically. If the term consists of multiple words that have potential variations, you will need to enter each variation as a synonym or spelling variation.
For example, if you add your product name Widget to a custom dictionary and specify that it is a noun, Search will also recognize Widgets, without having to enter the plural form separately. If you add Widget as a literal, only that precise form is recognized.
Is the Term a Misspelling of an Existing Dictionary Term
If your reports suggest that users are searching with a misspelled version of a dictionary term, you may want to add the misspelled version of the term to a custom dictionary.
However, before you add the term, make sure that you try a search with the misspelling; Search does include a spellchecking feature, which will attempt to correct the misspelled term. If Search can determine the correct form of the term, the search will work, and you do not need to add the term.
Note, however, that if the misspelled version of the term actually appears in the content, the spellchecker assumes that it is a valid term, does not correct it, and the search will return only the misspelled items, because those match exactly the term the user entered.
If your tests with the misspelled search term do not achieve good results, add the correct version of the term to a dictionary as a custom term, and also add the misspelled version or versions as spelling variations of that term.
Is the Term Part of a Larger Phrase
If the term appears in your content only as part of a larger phrase, add the entire phrase as a custom term. Note that you only need to add the phrase if the term appears in other forms (such as a plural) or has synonyms.
For example, cous cous is often written as one word, couscous, so cous cous should be added and given a synonym of couscous.
Similarly, Aloe vera can be referred to simply as aloe. Phrases such as this require careful consideration. Before adding it as a custom term, compare the results of a search on aloe vera to a search on just aloe, and see if the results are consistent and satisfactory. Since searches on catalog data are AND searches by default, searches on aloe vera may not return good results if the content contains only aloe. If this is the case, you should add aloe vera as a custom term, with aloe as a synonym. There is no need to enter vera as a synonym, since aloe vera is never referred to as just vera.
Note that if you define a phrase (a term containing more than one word) in a custom dictionary, that phrase becomes an unbreakable unit and will no longer match any of its separate parts and will not take any prefixes or suffixes at all. For example, if you define visa credit card as a term, the phrase will not match visa or credit card or even visa credit cards. It will only match the exact string visa credit card. If you want any variations of the phrase to match, you have to define all of those variations as synonyms. It is best not to add phrases to a custom dictionary except as a fix for actual problems that come up in search.
