sugar from milk, 1843, from French, coined 1843 by French chemist Jean Baptiste André Dumas (1800-1884) from Latin lac (genitive lactis) "milk" (from PIE root *g(a)lag- "milk") + chemical suffix -ose (2).
cow's milk contains about 4.7% lactose
lacteal
lactescence
lactic
lactivorous
lacto-
lactose
lacuna
lacunae
lacustrine
lacy
lad
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