' The blockchain is a global and decentralized ledger that stores information about a transaction and also verifies the data'
it is interesting that all these results from a google search about "what is blockchain" call it a "decentralized" ledger. like this one that you copied from Wikipedia!
well blockchain is simply a chain of blocks which is made using cryptography. it is used in a decentralized manner in bitcoin but from what i understand there is no reason to use it in a decentralized way. you can see that clearly in many centralized altcoins that are also using the blockchain technology. which leads me to say that a better word for it is
distributed ledger.
what the community is doing is this.
for the open decentralised(atbest) definition.. they call blockchain
for the closed / distributed within authorised userset definition.. they call DLT (distributed ledger technology)
however the way things are going where only one team get to dominate the direction of protocol changes and make demands that an upgrade is mandatory.. yea the old definition of blockchain is starting to lose its 'decentralisation' ethos