Definition

The remains of a bird after it has collided with an aircraft (in a bird strike), especially a turbine engine. 

The origin of the term appears to be U.S. military aviation slang and a combination of the words "snot" and "garbage".

Accident investigation

Following ingestion in a turbine engine, there is often very little of the bird left to identify the species. remains and swabs of samples taken from the aircraft are sent for analysis to determine the species by comparison with feathers on file and DNA analysis.

Determining the species involved can help investigators determine the circumstances that resulted in the bird strike and inform recommendations to avoid a recurrence - for example a change in bird control strategies, or arrival and departure routes.