BIP-156
Dandelion - Privacy Enhancing Routing.
Proposed hiding where a payment came from by passing it along a random chain of nodes before spreading it widely.
The usual way of spreading a payment lets spy nodes work out which node, and so which internet address, sent it. Dandelion would first send it along a random path, the 'stem', and then spread it normally, the 'fluff'.
Read BIP-156 in full on GitHubAll BIPs