Insert a Unicode Word Break ValueA Unicode word break value is one of the many Unicode properties that you can insert via the Insert Token button on the Create panel.

Every Unicode code point has exactly one value for the Grapheme_Cluster_Break property. This property is part of Unicode Standard Annex 29 (UAX 29) titled “Unicode Text Segmentation”. This property is used to determine the boundaries between words. Such a boundary is a word break. The property alone does not determine where the breaks are. Rather, the rules in UAX 29 use the values that the characters before and after a position in the text have for this property to determine whether there is a word break at that position.
It’s not very likely that you would need to match this property with a regular expression. You could use it to implement the rules in UAX 29 using regular expressions. But most regex flavors that support this property also support \b{wb} to match an actual word break according to UAX 29, or they have the mode modifier to make \b implement UAX 29 rather than a traditional word boundary. You can insert one of those with the Word Boundary (UAX 29) item in the Anchor submenu of the Insert Token menu.