In Google Adwords, broad match phrases can lead to your ads showing up for some very irrelevant queries. For instance, if your broad match phrase is ‘pink shoes’, your ad can show up for a wild assortment of queries like ‘ pink clown shoes’, ‘pink ballet shoes’, ‘pink scuba shoes’. While if you use phrase match, your ads may not get enough visibility for ‘pink shoes’. So Google has introduced ‘Broad Match Modifier’ to remedy this issue.
Here is an exert from the Adwords blog about this new feature:
Today we’re introducing the broad match modifier, a new AdWords targeting feature that lets you create keywords that have greater reach than phrase match and more control than broad match. Adding modified broad match keywords to your campaign can help you get more clicks and conversions at an attractive ROI, especially if you mainly use exact and phrase match keywords today.
To implement the modifier, just put a plus symbol (+) directly in front of one or more words in a broad match keyword. Each word preceded by a + has to appear in your potential customer’s search exactly or as a close variant. Close variants include misspellings, singular/plural forms, abbreviations and acronyms, and stemmings (like “floor” and “flooring”). Synonyms (like “quick” and “fast”) and related searches (like “flowers” and “tulips”) aren’t considered close variants.
The graphic above illustrates the relative reach of different keyword match type strategies. As you can see, modified broad match keywords match more searches than the equivalent phrase match keyword, but fewer searches than the equivalent broad match keyword. Match behavior also depends on the specific words you modify. For example, the keyword formal +shoes will match the search “evening shoes,” but the keyword +formal +shoes will not.

