Answer:
I'll do the plural first and put it on a parenthesis () then I'll do the definitions
Stratum- (strata) A horizontal layer of material especially one of several parallel layers arranged one of top of the other.
Retinoblastoma - (retinoblastomas also retinoblastomata) Malignant tumor of the eye involving the retina.
Decubitus- (decubiti) Area of the skin that becomes broken and painful caused by continuous pressure.
Disease- (diseases) any abnormal condition that disrupts the functions of body tissue, organ, or an entire organism.
Vena Cava- (venae cavae) A large vein that carries blood to the heart from other areas of the body.
Allergy- (allergies) An allergy occurs when someone's immune system reacts to specific substances in the environment that would usually be harmless to most people.
Metastasis- (metastases) the spread of cancer cells from the primary site of tumor development to lymph nodes and distant sites.