ho (Greek #3588)
the definite article; the (sometimes to be supplied, at others omitted, in English idiom)
KJV usage: the, this, that, one, he, she, it, etc.
Pronounce: ho
Origin: ἡ (hay), and the neuter τό (to) in all their inflections
Petros (Greek #4074)
a (piece of) rock (larger than 3037); as a name, Petrus, an apostle
KJV usage: Peter, rock. Compare 2786.
Pronounce: pet'-ros
Origin: apparently a primary word