Equity
Your share of the pot based on how often your hand would win if all remaining cards were dealt.
If you win 40% of the time in a $100 pot, your equity is worth $40. Equity ignores future betting, which is why players also talk about "equity realization": how much of that share you actually collect after position and skill. Check any matchup with our odds calculator.
Example
AK against QQ all-in preflop has about 43% equity.