immunity to a particular disease that is not innate but has been acquired during life; immunity can be acquired by the development of antibodies after an attack of an infectious disease or by a pregnant mother passing antibodies through the placenta to a 是什么意思 immunity to a particular disease that is not innate but has been acquired during life; immunity can be acquired by the development of antibodies after an attack of an infectious disease or by a pregnant mother passing antibodies through the placenta to a 怎么读