High Flier

What Does High Flier Mean?
A stock that has seen its share price - and subsequently its valuation - rise to high multiples on metrics such as current earnings and current sales. Usually, the rise will happen quickly, with the stock well outpacing the gains in the overall market during the same time period. Also, higher levels of volatility are usually found in high-flying stocks to go along with frequent spikes in trade volume. 

Investopedia explains High Flier
Many internet stocks were high fliers in the late 1990s, even though most had never turned a net profit. Investors were sold on the story of what kind of money the companies could earn in the future based on the ultra-rapid growth rates seen at the time.   

Many high-flying stocks tumble quickly; expectations can get well ahead of actual revenues and profits and as soon as a chink in the armour appears, short-term investors leave the stock in droves, sending shares plummeting.