The formation of a word from another word or base is called its derivation. Sort of like a "word" family tree as might be viewed in our world of genealogy. The following diagram shows such a derivation for our surname JONES.
When Alexander got around to taking the world by storm (334 - 325 BC), the Greek language became the language of the world. Around 285 BC, the scholars in Alexandria translated the Hebrew writings into the Greek language which is called the Septuagint. Little did they know that another group called the Romans would replace their language with that Latin. (265 BC - 44 BC)
It took the next 400 years for the Latin to be written by those of the Christian faith into the form that was to become the name JOHN. With the spread of Christianity (600 AD - 1100 AD) the name of JOHN took on its on significance. The Celtic Church, the Norman (French), the Anglo-Saxon and many other groups of folks took the name to give to their sons. Each language giving its own pronunciation and spelling. The Welsh of Celtic origins, had no "J" in their alphabet, and it took the Anglo-Saxon under Norman conquest to finally make the transliteration JOHN. [Welsh "J" sound was written "Si".] When the three Edwards [I,II, III], and finally the Tudors, ended the process of Welsh annexation [The Act of Union, 1536] the name JOHN was transliterated to become the surname JONES. This was often the case when one of those Welshmen told their names in the English courts as William ap John ap Thomas ap Rys ap Peter... are you kidding me...I am not going to write that down in these English records. Besides, you have to speak English now, and that sounds like JONES to me!
Well, there you have it... the derivation of the JONES surname. Who would have believed it?