without apparent forethought or prompting or planning; "an unplanned economy"; "accepts an unplanned order"; "an unplanned pregnancy"; "unplanned remarks"
an establishment consisting of a building or complex of buildings where an organization for the promotion of some cause is situated
a custom that for a long time has been an important feature of some group or society; "the institution of marriage"; "the institution of slavery"; "he had become an institution in the theater"
an organization founded and united for a specific purpose