inoculate

infuse, suffuse, imbue, ingrain, inoculate, leaven mean to introduce one thing into another so as to affect it throughout. infuse implies a pouring in of something that gives new life or significance <new members infused enthusiasm into the club>. suffuse implies a spreading through of something that gives an unusual color or quality <a room suffused with light>. imbue implies the introduction of a quality that fills and permeates the whole being <imbue students with intellectual curiosity>. ingrain , used only in the passive or past participle, suggests the deep implanting of a quality or trait <clung to ingrained habits>. inoculate implies an imbuing or implanting with a germinal idea and often suggests stealth or subtlety <an electorate inoculated with dangerous ideas>. leaven implies introducing something that enlivens, tempers, or markedly alters the total quality <a serious play leavened with comic moments>.

Similar to the way that we use “eye” for the undeveloped bud on a potato, the Romans used the Latin word oculus, “eye,” to mean “bud of a plant.” Having learned that the oculus or bud from one plant can be grafted onto another, the Romans derived the verb inoculare from oculus to refer to the process of grafting. English borrowed this verb as inoculate with the same meaning. Introducing a small amount of material to make a person immune to a disease is like implanting a bud, so the verb inoculate was also used for this procedure.