Blood-splattered is a description meaning to be covered in blood. for example, The zombie's clothes were blood-splattered and torn.

Blood-splattered is where blood from someone has shot out of their body and hit a person or an object. The pattern left is called 'blood splatter' and it means a lot of blood. As per Valerie's example. There are two terms to note, which are quite similar. Blood spatter is where a small quantity of blood is spread (for instance) if someone coughs and a bit of blood hits the nurse's uniform. Blood splatter is where there is a lot of blood, for example where someone is shot and the blood gushes onto someone nearby or where the blood pumps out and forms a pool around a body. Terribly gruesome question!

there were many drops of blood on it. https://www.dreamstime.com/royalty-free-stock-photos-blood-splattered-image910248

Blood-spattered; means Covered with drops or spots of blood. 'his body was found in a blood- spattered room'