Is it ensure, insure, or assure?
plural (and now the usual form) of auspice; 1530s, "observation of birds for the purpose of taking omens," from French auspice (14c.), from Latin auspicum "function of an auspex" (q.v.). Meaning "any indication of the future (especially favorable)" is from 1650s; earlier (1630s) in extended sense of "benevolent influence of greater power, influence exerted on behalf of someone or something," originally in expression under the auspices of.
1590s, "one who observes flights of birds for the purpose of taking omens," from Latin auspex "interpreter of omens given by birds," from PIE *awi-spek- "observer of birds," from *awi- "bird" (see aviary) + *spek- "to see" (see scope (n.1)). Connection between birds and omens also is in Greek oionos "bird of prey, bird of omen, omen," and ornis "bird," which also could mean "omen."