IPA: /ˌɛf.ləˈrɛs/
KK: /ɛfˈlɔrɛs/
To change from a solid or liquid state into a powdery form, often due to losing water, or to produce flowers or blossoms.
The salt began to effloresce when left out in the open air for too long.
Past: effloresced
Past Participle: effloresced
Effloresce is formed from "ex-" (meaning out) and "florescere" (meaning to bloom or blossom). The word describes the process of blooming or flowering out, often used in the context of plants or crystals.
Think of something 'blooming out' ('ex-') — that's why effloresce means to bloom or blossom.