Merchants with too broad or no category

I've been searching the forum with no luck. Seems I read there was a way to create an if/then type statement that can be used instead of category mapping?
I have several merchants whose categories are so vague or non existent as to be useless. Home appliances are all grouped under home or kitchen. Is there a way to pull from description to create categories. For example, if description has "coffee maker", then create category name Coffee Makers.
To go through and change with category mapping wouldn't work if a merchant uses one or two categories or none at all.

Thanks, Diana