say it: LAK-tohs
lactose is a noun meaning "a sugar comprising one glucose molecule linked to a galactose molecule; occurs only in milk". It carries one recorded sense.
a sugar comprising one glucose molecule linked to a galactose molecule; occurs only in milk
“cow's milk contains about 4.7% lactose”
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for lactose come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.