Fallback Search Trigger
Fallback searches are the search options Alfred presents to you when he can't find results locally on your Mac. By default, these are Google, Wikipedia and Amazon.
However, if you want to add alternatives, you can create a Fallback Search trigger to add your own workflows to Alfred's fallback search options.
Fallback Search Example Use
I created a Fallback Search for the Dictionary app, so that if I start typing a word that doesn't match a result on my Mac, I can search for it in Dictionary as you can see in the fallback searches below.
This is done by creating a workflow where I joined a Fallback Search object to an Open URL object, where the URL to open is dict://{query}. This launches Dictionary.app with the query filled in.
The workflow trigger is then added under Alfred's Default Results's "Setup fallback results" button.
Next time you search for a word that doesn't result in any local results being found, Alfred will show you the fallback searches, including your newly added custom fallback search.
Download the Example Workflow
To take a look at how the example above was created, you can download the Dictionary Fallback Search workflow.