Of is defined as to indicate ownership or distance from
something.(preposition) See of in Webster's New World College
Dictionary Origin: ME < OE, unstressed var. of af, æf, away
(from); akin to Ger ab < IE base *apo-, from, away from > L ab
(see ab-), Gr apo- See of in American Heritage Dictionary 4
Origin: Middle English Origin: , from Old English; see apo- in
Indo-European roots. Usage Note: Grammarians have sometimes
objected to the so-called double genitive construction, as in a
friend of my father's; a book of mine. But the construction has
been used in English since the 14th century and serves a useful
purpose. It can help sort out ambiguous phrases like Bob's
photograph, which could refer either to a photograph of Bob
(that is, revealing Bob's image) or to one in Bob's possession.
A photograph of Bob's can only be a photo that Bob has in his
possession, which may or may not show Bob's image. Moreover, in
some sentences the double genitive offers the only way to
express what is meant. There is no substi