incubation period

== English == === Etymology === Since 1850s, from earlier period of incubation, attested in that now obsolete sense since late 1820s, which is a calque of French période d'incubation (attested since mid-1810s), itself a calque from Latin periodus incubationis (attested since 1770s). === Noun === incubation period (plural incubation periods) (epidemiology) The time elapsed between an exposure to a pathogenic organism, a chemical or radiation, and the appearance of signs and symptoms. 1854, Medical Notes on the Wreck of the San Francisco, by William P. Buel ==== Usage notes ==== Not to be confused with incubation time, which has a different meaning. ==== Translations ====