Replayable security against Chosen-Ciphertext Attack (noted 'RCCA') is a security notion in cryptography that relaxes the older notion of Security against Chosen-Ciphertext Attack (CCA, more precisely adaptive security notion CCA2) : all CCA-secure systems are RCCA secure but the converse is not true.
It has been introduced in 2003 in a research publication by Ran Canetti, Hugo Krawczyk and Jesper B. Nielsen. The claim is that for a lot of use cases, CCA is too strong and RCCA suffices.
Nowadays a certain amount of cryptographic scheme are proved RCCA-secure instead of CCA secure.
References
RCCA Security Wikipedia(Text) CC BY-SA