Man-in-the-Middle Attack (MITM): A man-in-the-middle attack (MITM) attack is a general term for a cyber attack where a perpetrator positions himself in a conversation between two parties either to secretly eavesdrop.

Margin Call: When an investor’s account value falls below the margin maintenance amount.

Margin Trading: A practice where a trader uses borrowed funds from a broker to trade a cryptocurrency.

Market: An area or arena, online or offline, in which commercial dealings are conducted.

Market Capitalization/Market Cap/MCAP: Total capitalization of a cryptocurrency’s price. It is one of the ways to rank the relative size of a cryptocurrency.

Market Maker, Market Taker: The maker places an order (to buy or sell at a quoted price), while a taker accepts that placed order (to execute the buy or sell at the quoted price)

Market Order/Market Buy/Market Sell: A purchase or sale of a cryptocurrency on an exchange at the current best available price.

Market Signal: Through signalling, market participants are essentially creating a volatile market which can help to point out the opportunities to the investors.

Masternodes: Masternodes are a server maintained by its owner, somewhat like full nodes, but with additional functionalities such as anonymizing transactions, clearing transactions, and participating in governance and voting. It was initially popularized by Dash to reward owners of these servers for maintaining a service for the blockchain.

Max Supply: The best approximation of the maximum amount of coins that will ever exist in the lifetime of the cryptocurrency.

MCAP: Short for market capitalization

Miner: A group of computers that add new transactions to blocks and verify blocks created by other miners. Miners collect transaction fees and are rewarded with new bitcoins for their services. Mining is a zero sum game and the winner takes all.

Multi-Sig: Multi-signature (or multisig for short) refers to requiring multiple keys to authorize a Bitcoin transaction, rather than a single signature from one key. It has a number of applications.

Mempool: A mempool (a contraction of memory and pool) is a cryptocurrency node's mechanism for storing information on unconfirmed transactions. It acts as a sort of waiting room for transactions that have not yet been included in a block.

Merkle Tree: A tree structure in cryptography, in which every leaf node is labelled with the hash of a data block and every non-leaf node is labelled with the cryptographic hash of the labels of its child nodes. Hash trees allow efficient and secure verification of the contents of blockchains, as each change propagates upwards so verification can be done by simply looking at the top hash.

MetaMask: An online digital wallet that allows users to manage, transfer and receive Ethereum, operating as an extension to a regular browser.

Metaverse: A metaverse is a digital universe that contains all the aspects of the real world, such as real-time interactions and economies. It offers a unique experience to end-users.

M of N: The number of cosigners that must provide signatures (M) out of the total number of cosigners (N) in order for a multi-signature bitcoin transaction to take place. A common M of N value is "2 of 3" meaning two of the three cosigners' signatures are required.

MicroBitcoin (uBTC): One millionth of a bitcoin or 0.000001 of a bitcoin. Often confused as a fork of Bitcoin.

Micropayment: A micropayment is essentially a small transaction that is carried out online and can be as small as a fraction of a cent.

Microtransaction: A business model where very small payments can be made in exchange for common digital goods and services, such as pages of an ebook or items in a game.

Mineable: Some cryptocurrencies have a system through which miners can be rewarded with newly-created cryptocurrencies for creating blocks through contributing their hash power. Cryptocurrencies with this ability to generate new cryptocurrencies through the process of confirmation is said to be mineable. * Not Mineable Some cryptocurrencies are generated only through other mechanisms, such as annual inflation through staking. These cryptocurrencies are said to be not mineable.

Mining: A process where blocks are added to a blockchain, verifying transactions. It is also the process through which new bitcoin or some altcoins are created.

Mining Contract: Another term for cloud mining, where users can rent or invest in mining capacity online.

Mining Difficulty: The mining difficulty of a cryptocurrency is how difficult it is to find the right hash for the next block.

Mining Farm: A mining farm is when a group of miners mine together for a variety of advantageous reasons, like energy use.

Mining Pool: An arrangement where a number of miners pool their resources to increase their chances of finding the next block.

Mining Reward: The income that miners receive after finding and validating a block.

Mining Rewards: Mining rewards are the rewards that crypto miners receive for mining a new block on the blockchain.

Mining Rig: Equipment that is used for mining cryptocurrencies.

Mt. Gox: Bitcoin’s first major exchange. It was shut down in February 2004 after losing around 850,000 bitcoin.

Multisignature: Multisignature crypto wallets require more than a single signature to sign a transaction.

By Stephen Whitelaw (