Accumulator: An accumulator or ‘ACCA’ is a series of four or more bets that combines into a single one. It does not pay out unless all bets win. Payouts are typically large in accumulators, to reflect the increased risk, which is multiplied by the different elements of the bet. You can also take out ‘Acca Insurance’ to cover losses when placing an accumulator.
Arb / Arbitrage: An Arb is where the bettor places a bet for and against a particular outcome, in order to ensure a profit whatever the outcome.
Vig / Vigorish, aka ‘the Juice’ / ‘cut’ / ‘take’ / ‘under-take’ = This is the fee that is charged by the betting house or bookmaker, for processing and accepting the bet placed by the bettor.