Bitcoin glossary

Bitcoin terms in Kiswahili and English, used the same way across every lesson.

address (anwani): A string you give someone so they can send you bitcoin, like an M-Pesa phone number.
backup (nakala ya akiba): A copy of your seed phrase kept somewhere safe so you can restore your wallet.
bitcoin: Digital money that no government or company issues. Its rules live in open-source software run by thousands of computers around the world.
block (bloku): A batch of transactions added to the blockchain about every 10 minutes.
blockchain: The shared record of every Bitcoin transaction, kept by nodes around the world.
BOLT11: The standard for Lightning invoices that start with lnbc (or lnbcrt on regtest).
chama: A group of people who save or invest together under rules they agreed on.
channel (chaneli): A payment link between two Lightning nodes, locked by a Bitcoin transaction.
commitment transaction (muamala wa ahadi): A signed transaction holding a channel's current balances; every payment makes a new one.
confirmation (uthibitisho): A transaction gets one confirmation when it enters a block; each later block adds another.
custodial wallet (pochi ya mtunzaji): A wallet where a company or another person holds the keys for you.
descriptor: A short description of which addresses a wallet owns and how to spend them.
ecash: Digital notes that stand for bitcoin held by a federation. Payments with them are private.
exchange (soko la kubadilishia): A company that sells you bitcoin for shillings or buys it from you; usually a custodian.
federation (shirikisho): A group of guardians who hold bitcoin together; most of them must agree before money moves.
Fedimint: Open-source software that lets a community run a federation that holds bitcoin together and issues ecash.
fee (ada): A small amount you pay to get your transaction into a block or routed over Lightning.
force close (kufunga kwa nguvu): Closing a channel alone by publishing a commitment transaction; your funds wait for a timelock.
gateway (lango): A Lightning node that connects a Fedimint federation to the Lightning Network.
gossip: Messages nodes pass on about existing channels and nodes, so each can build a map of the network.
guardian (mlinzi): A member of a federation who runs a server and holds part of the keys.
halving (upunguzaji nusu): Every 210,000 blocks (about four years) the new-bitcoin reward for miners is cut in half.
HTLC: Hash time-locked contract: a payment that unlocks only with the right secret before a deadline.
inflation (mfumuko wa bei): Prices rising over time, so the same money buys less.
invoice (ankara): A Lightning payment request, often shown as a QR code, with an amount and an expiry time.
Lightning Network (mtandao wa Lightning): A network on top of Bitcoin for fast payments with very small fees.
liquidity (ukwasi): How much can be sent (outbound) or received (inbound) over a channel.
mempool: The queue of transactions waiting to get into a block.
mining (uchimbaji): Computers competing to add the next block, paid in new bitcoin and fees.
multisig: A setup where several signatures are needed to spend bitcoin, for example 2 of 3.
node (nodi): A computer running Bitcoin or Lightning software that checks every rule for itself.
onion routing (upitishaji wa kitunguu): Wrapping payment instructions in layers of encryption so each node only learns the next hop.
open source (programu huria): Software whose code anyone can read, check and improve.
phishing (hadaa ya mtandaoni): A fake message or website pretending to be a real service to steal your secrets.
preimage: The secret whose hash is the payment hash. Revealing it proves the payment arrived.
private key (ufunguo binafsi): A secret number that signs your payments. Never give it to anyone.
probing (kupima kwa majaribio): Sending payments that cannot complete to learn whether a route has enough liquidity.
public key (ufunguo wa umma): A number derived from your private key. Others use it to check your signature without learning your secret.
pull request: A proposed change to a GitHub project, reviewed before it is merged.
QR code (msimbo wa QR): A square of dots a phone camera can read, often holding an address or invoice.
regtest: A private Bitcoin test network you control, where blocks are mined instantly.
sats: The smallest unit of bitcoin. One bitcoin is 100 million sats.
scam (utapeli): A trick to fool you into handing over money or secrets.
seed phrase (maneno ya siri): 12 or 24 words that can restore every key in your wallet. Whoever knows them owns the money.
self-custody (kujitunzia): Holding your own keys, without relying on anyone else to keep them.
transaction (muamala): A signed message that moves bitcoin from old outputs to new owners.
UTXO: Unspent transaction output: a piece of bitcoin you can spend.
volatility (kupanda na kushuka kwa bei): How quickly and how far a price moves, up or down.
wallet (pochi): An app or device that stores your keys and lets you send and receive bitcoin. It doesn't hold the coins themselves.
whitepaper (karatasi nyeupe): Satoshi Nakamoto's nine-page paper (2008) that first described Bitcoin.