Definition of Agent Orange

Agent Orange: An herbicide and defoliant containing 2,4-D and 2,4,5-T and trace amounts of dioxin. Agent Orange was used as a defoliant in the Vietnam War. There has been concern about Agent Orange as a carcinogen and teratogen (cause cancer and birth defects).
The Institute of Medicine of the National Academies in the US has found "sufficient evidence" of an association between exposure to Agent Orange and the risk of developing chronic lymphocytic leukemia (CLL), non-Hodgkin lymphoma (NHL), Hodgkin disease, and soft tissue sarcoma.

Definition of Actinic

Actinic: Referring to the ultraviolet (UV) rays from sunlight and UV lamps. Sunburn is an actinic burn. An actinic keratosis is a skin lesion that is the consequence of chronic sun exposure. From the Greek "aktis" meaning "ray."

Definition of Accelerated phase of leukemia

Accelerated phase of leukemia:
Refers to chronic myelogenous leukemia (CML) that is progressing. The number of immature, abnormal white blood cells in the bone marrow and blood is higher than in the chronic phase but not as high as in the blast phase.