From Wiktionary, the free dictionary
peko
- locative singular of pe
From peki (“to sin”) + -o.
peko (accusative singular pekon, plural pekoj, accusative plural pekojn)
- sin (in religious sense, or just a bad act)
- fault (defect) ??
- peka (“sinful”, adjective)
- pekema (“sinning, wicked”, adjective)
- peki (“to sin”)
- senpeka (“innocent, sinless”, adjective)