Cashable bonus means you can withdraw both bonus and deposit after you meet the wagering requirements.

Sticky/non cashable is a bonus that can't ever be withdrawn from the casino.

Example: A casino offers sticky (non cashable) bonus of 200% up to $200. That means if you deposit $100 you will get $200 bonus, giving you $300 as starting balance. After meeting wagering requirements, and asking for withdrawal, the casino will deduct the $200 bonus from your account. So if you have $400 in your account ($200 is sticky bonus, $100 is your deposit, and $100 are your winnings) and try to withdraw all your money, the casino will send you only $200, deducting $200 bonus from your account, leaving you with $100 profit. But if you for example have only $220 left in your account after meeting wagering requirements, you will be allowed to withdraw only $20, since $200 is sticky. That means youll end up losing $80.