1. noun
a) A chemical, such as sodium hypochlorite or hydrogen peroxide, or a preparation of such a chemical, used for disinfecting or whitening.
b) A variety of bleach.
2. verb
Once coral bleaching begins, corals tend to continue to bleach even if the stressor is removed.
b) For corals to lose color due to stress-induced expulsion of symbiotic unicellular algae.
Wikipedia foundation.