Wiktionary
n. (context grammar English) A case used to indicate movement '''into''' something; for example, ''into the house''. Some languages that make use of the illative are Finnish, Hungarian, and Quechua.
Wikipedia
Illative ( abbreviated ; from Latin illatus "brought in") is, in the Finnish language, the Estonian language, the Lithuanian language, and the Hungarian language, the third of the locative cases with the basic meaning of "into (the inside of)". An example from Hungarian is "a házba" (into the house, with "a ház" meaning "the house"). An example from Estonian is "majasse" and "majja" (into the house), formed from "maja" (a house). An example from Finnish is "taloon" (into the house), formed from "talo" (a house).