Hi welcome to healthcare magic ....
mean in simple language wound , because the brain had an injury
there is a wound in the brain , which technically is called contusion.
Small Heamorrhagis component meand - because of wound there is small bleed , that heamorrhage.
Eg when we fall down on our knees , we have a wound - red , painful area (similarly ccontusion) , some time if the injury is great then it may bleed from the wound (similarly small heamorrhages)
left parieto occipital area - is area of brain , i.e on the side and back on left side.
Subarachnoid Bleed - Subarachnoid is a space in between the brain and the layers covering brain. Brain is covered by 3 layers , one such layer is called arachnoid layer , so space below arachnoid layer is called sub(below) arachnoid space, where there is some bleed.
Resolving or resolved means its healing up ...
Hope i was helpful.
Thank you . have a gr8 day.