Father:
 
The world father has a range of meanings such as, a male parent of a child, an important figure in history responsible for the creation of something; "the father of abstract art." The founding father. It can be a verb: to father someone. In Christianity the father refers to God.  Father is the name given to a priest. It can also be used to show respect:  the oldest members of a society, the fathers. (Elders, leaders)
 
The word "father" can be traced back to the Latin word 'pater'.

There was a process called "the great consonant shift" which meant that related languages began to change and letters such as 

"p" began to be pronounced as "f" or "v",

"t" began to be pronounced as "d"

 

This explains why the Latin word "pater" translates so similarly into various European languages as:

vater - German

faeder - Old English
padre - Italian & Spanish

Middle English: Father

Widespread phonetic shift in Middle English that turned -der to -ther in many words