Lichen is the symbiotic association of a fungus (the mycobiont, which provides shelter and structure for the partnership or symbiosis), with an alga or cyanobacterium (the phoâ¦tobiont, also known as the phycobiont, which provides the food for the partnership from photosynthesis).
Some radiation therapy delivery methods include: 1  External beam radiation therapy â radiation is directed from a machine outside the body onto cancerous cells within the body.  Internal radiation therapy â radioactive material is placed (via a catheter or other carrier) directly into or near a tumor.
Related to radiation oncology: radiation therapy. 1. the medical specialty concerned with the use of ionizing radiation in the treatment of disease; 2. the medical specialty of radiation therapy; 3. the use of radiation in the treatment of neoplasms. Synonym(s): radiotherapy, therapeutic radiology. n.