efflorescent

noun

1. a flowering; blooming
2. the time of flowering
3. the peak or fulfillment, as of a career
4. Chem.
   1. the changing of certain crystalline compounds to a whitish powder or powdery crust through loss of their water of crystallization
   2. the powder or crust thus formed
5. Med. an eruption on the skin; rash or other skin lesion

Origin: Fr < L efflorescens, prp. of efflorescere: see effloresce