Help With Regular Expressions

The dictionary supports Regular Expression (RegEx) searches. These provide a very powerful way of searching the dictionary but may not be necessary for all users and can be difficult to understand at first.

A Regular Expression search is entered in the same way as any other search. When using regular expressions we usually recommend that you select the Part Word and Accent Sensitive options. This is because the Whole Word and Accent Insensitive options insert extra regular expressions into your search and this can have unexpected results when used with your own Regular Expression searches, preventing you finding what you're looking for.

Here are some examples of what Regular Expression searches can do:

1. Lenition
Using the asterisk, you can locate both lenited and unlenited forms of a word in the same search. For example:

2. Alternate Letters
If you want to locate words that you know suffer from spelling alternations, you can use the following ( | ) to locate both in the same search.  For example:
3. Words Ending or Beginning in...
If you use [[:>:]] or [[:<:]], you can search for words ending or beginning in a particular string.  For example:
4. Vowel Permutations
There are various ways in which you can search for words with varying vowels between consonants.  For example:

5. Phrase Search
To search for a phrase (as in, two words which are not next to each other), such as a cat may look at the king, you use the following expression:


This will find all entries that contain the word cat then anything else then the word king. To search for a different pairing, simply replace the words for cat and king.

The % wildcard character which could be used in older versions of the dictionary is still supported.

6. More About RegEx
There are several different dialects of Regular Expression which are implemented in slightly different ways. The dictionary uses MySQL Regular Expressions and more information about these can be found here.

There are also several good general resources online explaining Regular Expressions in detail, for example here.