1610s, "brooding," from Latin incubationem (nominative incubatio) "a laying upon eggs," noun of action from past participle stem of incubare "to hatch," literally "to lie on, rest on," from in- "on" (see in- (2)) + cubare "to lie" (see cubicle). The literal sense of "sitting on eggs to hatch them" first recorded in English 1640s.
incubation in·cu·ba·tion (ĭn'kyə-bā'shən, ĭng'-)
n.
The act of incubating or the state of being incubated.
The maintenance of controlled environmental conditions for the purpose of favoring the growth or development of microbial or tissue cultures.
The maintenance of an infant, especially a premature infant, in an environment of controlled temperature, humidity, and oxygen concentration in order to provide optimal conditions for growth and development.
The development of an infection from the time the pathogen enters the body until signs or symptoms first appear.
the maintenance of uniform conditions of temperature and humidity to ensure the development of eggs or, under laboratory conditions, of certain experimental organisms, especially bacteria. The phrase incubation period designates the time from the commencement of incubation to hatching. It also is the time between the infection of an animal by a disease organism and the first appearance of symptoms.