Smurfing is a money-laundering technique involving the structuring of large amounts of cash into multiple small transactions. Smurfs often spread these small transactions over many different accounts, to keep them under regulatory reporting limits and avoid detection.
In the Blockchain world, an attacker can easily create multiple wallets and can send small transactions over these wallets.
https://singhharsh246.medium.com/crypto-smurfing-7de5651650fe