Broad Match is a form of “keyword matching” and refers to the matching of a search listing or advertisement to selected keywords in any order.
This means if selected keywords are “running shoes”, then ads or a search listing may be displayed if the users searches upon the following example keywords:
Any Order: “shoes running”
Synonym: “running sneakers”
Plural, Singular: “running shoe”
Broad match terms are less targeted than exact or phrase matches.