What is the most aggressive ETF?

Could you please explain what the term 'aggressive ETF' actually means? Among the various ETFs available in the market, which one stands out as the most aggressive? What characteristics does this ETF possess that make it stand apart from others? Is it related to high risk-high return investments? How does its performance compare to other ETFs in terms of volatility and potential returns? Could you also provide an example of such an aggressive ETF and its track record?