Definition of "actinic" in English

adjective

1. Related to radiation; used most often in reference to light, especially in the ultraviolet range.

2. (by extension) Harsh and bright, especially blindingly so.

3. (medicine) Caused by extensive exposure to ultraviolet light.

   • In medicine, actinic keratoses usually occur in sundamaged skin and exhibit hyperkeratosis.

4. (chemistry, photography) Of or relating to actinism, the range of photochemical effects produced by exposure to electromagnetic radiation, particularly sunlight.

5. Composed of actin.