Transformation

• a radiation change in morphology among homologous structures.
  Source: Anthromorphemics
• conversion of a normal cell into a cancerous cell; also refers to the uptake and incorporation of exogenous DNA by a cell
  Source: Jenkins, John B. 1990. Human Genetics, 2nd Edition. New York: Harper & Row
• In prokaryotes, the natural or induced uptake and expression of a foreign DNA sequence--typically a recombinant plasmid in experimental systems. In higher eukaryotes, the conversion of cultured cells to a malignant phenotype--typically through infection by a tumor virus or transfection with an oncogene.
• The change that a normal cell undergoes as it becomes malignant.