(colloquial) a variation of honest to
God, really, truly or genuinely; used to emphasize one's sincerity or truthfulness.
Pete is a euphemism for
God.
—PDC Volume 5 Approved Glossary, —PDC Volume 4 Approved Glossary, —PDC Volume 6 Approved Glossary, —State of Man Congress Approved Gls (14.5.92)