noun
: a use that is limited to arise on the happening of a future event and is not dependent on any preceding use or estate and that is not in derogation of any prior estate or limited on a particular estate
noun
: a use that is limited to arise on the happening of a future event and is not dependent on any preceding use or estate and that is not in derogation of any prior estate or limited on a particular estate
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012