Quiz: Remember the definition of mal de mer?


[ef-luh-res-uh ns] /ˌɛf ləˈrɛs əns/
the state or a period of flowering.
an example or result of growth and development:
These works are the efflorescence of his genius.
  1. the act or process of efflorescing.
  2. the resulting powdery substance or incrustation.
Pathology. a rash or eruption of the skin.
1620-30; < French < Medieval Latin efflōrēscentia. See effloresce, -ence Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
Cite This Source
Examples from the web for efflorescence
  • The concrete located on the downstream face of the right spillway abutment has areas of efflorescence.
  • Clean and remove all paint, efflorescence, sealant and corrosion staining on masonry.
  • Remove efflorescence, loose and chalking plaster or finishing materials.
British Dictionary definitions for efflorescence


a bursting forth or flowering
(chem, geology)
  1. the process of efflorescing
  2. the powdery substance formed as a result of this process, esp on the surface of rocks
any skin rash or eruption
Derived Forms
efflorescent, adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Cite This Source
Word Origin and History for efflorescence

1620s, from French efflorescence, from Latin efflorescentem (nominative efflorescens), present participle of efflorescere (see effloresce).

Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
efflorescence in Science
  1. A whitish, powdery deposit on the surface of rocks or soil in dry regions. It is formed as mineral-rich water rises to the surface through capillary action and then evaporates. Efflorescence usually consists of gypsum, salt, or calcite.

  2. See anthesis.

The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source
Encyclopedia Article for efflorescence

spontaneous loss of water by a hydrated salt, which occurs when the aqueous vapor pressure of the hydrate is greater than the partial pressure of the water vapour in the air. For example, because the vapour pressures of washing soda (Na2CO310H2O) and Glauber's salt (Na2SO410H2O) normally exceed that of the water vapour in the atmosphere, these salts effloresce (i.e., lose all or part of their water of hydration), and their surfaces assume a powdery appearance. Hydrated cupric sulfate, or blue vitriol (CuSO45H2O), the aqueous vapour pressure of which is lower, undergoes efflorescence only if the air in contact with it is relatively dry. See also deliquescence.

Learn more about efflorescence with a free trial on
Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
Cite This Source

Word of the Day

Difficulty index for efflorescence

Few English speakers likely know this word

Word Value for efflorescence

Scrabble Words With Friends

Nearby words for efflorescence