v.
Pronunciation: ˌ e-fl ə - ' res
Function: intransitive verb
Inflected Form: -resced ; -resc · ing
Etymology: Latin efflorescere, from ex- + florescere to begin to blossom ― more at FLORESCENCE
Date: 1775
1 : to burst forth : BLOOM
2 a : to change to a powder from loss of water of crystallization b : to form or become covered with a powdery crust <bricks may effloresce owing to the deposition of soluble salts>