laitance

[ leyt-ns ]
/ ˈleɪt ns /

noun

a milky deposit on the surface of new cement or concrete, usually caused by too much water.

Origin of laitance

1905–10; special use of French laitance milt, equivalent to lait milk (< Latin lact-, stem of lac) + -ance -ance
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019