Dust / Dust Limit
“Dust” is a colloquial term used to describe a UTXO with a satoshi amount so small it cannot be propagated from Lightning Network back onto the Bitcoin blockchain. Each individual node may decide what their personal dust limit is – or what they decide to be nominally dispensable satoshi amounts – but it must be higher than 546 satoshis. Anything lower than that will not be relayed by Bitcoin nodes running v0.10 default settings.
In Lightning Network channels, both parties must agree on what their channel’s dust limit is so before they can close a channel. In this way, both parties can feel comfortable with the dust they are leaving on the channel.
It is possible to consolidate dust from all your channels and Bitcoin and Lightning Network.