highflier

or high-fli·er, high·fly·er, high-fly·er

[hahy-flahy-er]

noun

a person who is extravagant or goes to extremes in aims, pretensions, opinions, etc.
a person or thing that flies high.
a stock, often speculative, whose price moves up or down widely.

Origin of highflier

First recorded in 1680–90; high + flier
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019