Final answer:
A blood stain resulting from a gunshot is known as an impact stain, which is identified through its pattern and can provide significant details for forensic analysis.
Step-by-step explanation:
If you find a blood stain that you know was caused by a gunshot, the blood stain would be considered an impact stain. This type of stain results from the force of an impact that causes blood to be thrown from an object, such as a bullet in this case.
These stains can provide valuable information about the direction from which the blood came and the force of the impact, which are crucial aspects in forensic investigations, especially in cases involving gunshots.