ret·i·no·blas·to·ma
| \ ˌre-tə-nō-ˌbla-ˈstō-mə
\
plural retinoblastomas
also retinoblastomata\ ˌre-tə-nō-ˌbla-ˈstō-mə-tə
\
: a malignant tumor of the retina that develops during childhood, is derived from retinal germ cells, and is associated with a chromosomal abnormality