Self-synchronizing stream cipher
A stream cipher that finds its keystream again on its own after bits have been lost.
A self-synchronizing stream cipher derives its keystream from a window of recent ciphertext symbols rather than from a separate counter. If the receiver loses or gains a bit, the state is refilled from the incoming ciphertext, and after a bounded number of symbols the two sides agree again. Only the symbols inside that window are lost.
Cipher feedback mode is the textbook example. The price is that an error spreads for a while and every symbol costs a block cipher call, which is slow for bulk data. The property suits links that drop or insert bits, where a synchronous cipher would need the whole stream restarted.