Definition of invest:
"the contributors to the Wikipedia and Wiktionary projects have invested countless hours into this resource.."
(n) :
an unnamed tropical weather pattern "to investigate" for development into a significant (named) system. A temporary designation by the U.S. Joint Typhoon Warning Center and . Internal jargon (possibly teletype abbreviation) in the 1980's. Appears today on some tracking maps, e.g. tropical storm advisories at the . Designation, e.g. 91e
, is a cyclic number (90-99) and a letter suffix for oceanic region: