Word Origin & History
prospermid-15c., from O.Fr. prosperer (14c.), from L. prosperare "cause to succeed, render happy," from prosperus "favorable, fortunate, prosperous," perhaps lit. "agreeable to one's wishes," from Old L. pro spere "according to expectation," from pro "for" + abl. of spes "hope," from PIE base *spei- "to flourish,
succeed."