user10084: There’s a lot of reference of "bitcoin node" in official FAQ or elsewhere.
But, what is exactly a bitcoin node ?
Is it a client like Bitcoin-qt or is it only a miner ? Or both ?

user5757: "Node" refers to any computer that's running Bitcoin client software and participating in the peer-to-peer network by relaying transactions and blocks. It could also be mining, but it doesn't  have to.

user10621: Bitcoin node refers to a "full" client. A "full" client is a client that owns the block chain and that is sharing blocks and transaction across the network. In opposite a Lightweight client can not be considered as a node because he doesn't share the block chain with the network.
Bitcoin network uses a client to client network infrastructure so there is no difference between a mining client and a non-mining client, they don't have any privileges.

10084: <p>There’s a lot of reference of "bitcoin node" in <a href="https://en.bitcoin.it/wiki/FAQ" rel="noreferrer">official FAQ</a> or <a href="http://getaddr.bitnodes.io/" rel="noreferrer">elsewhere</a>.</p>

<p>But, what is exactly a bitcoin node ?</p>

<p>Is it a client like <a href="http://bitcoin-qt.net/en/download.html" rel="noreferrer">Bitcoin-qt</a> or is it only a miner ? Or both ?</p>
 5757: <p>"Node" refers to any computer that's running Bitcoin client software and participating in the peer-to-peer network by relaying transactions and blocks. It could also be mining, but it doesn't  have to.</p>
 10621: <p>Bitcoin node refers to a "full" client. A "full" client is a client that owns the block chain and that is sharing blocks and transaction across the network. In opposite a Lightweight client can not be considered as a node because he doesn't share the block chain with the network.</p>

<p>Bitcoin network uses a client to client network infrastructure so there is no difference between a mining client and a non-mining client, they don't have any privileges.</p>
