Roger wrote:
More obvious in Italian ;-)

Pietro=Peter, Pietra=Rock.

i.e. The name Peter is derived from stone or rock.

Allthougth I'm sure some highbrow could give you a more fundamental
Latin or Greek explanation!

In Greek:
Petros = Peter = Rock[1]
hence 'petrified' etc.

Theo
(not claiming to be highbrow, just Greek :-)

[1] In Modern Greek rock is 'petra' (feminine). It's not 'stone', which is
'lithos' (eg lithography)