Inherited from Old Ruthenian пе́кло (péklo, “hell”), from Old East Slavic пькълъ (pĭkŭlŭ, “pitch, tar, resin”), from Proto-Slavic *pьkъlo (“pitch, tar, resin”). The meaning "hell" is a semantic loan from Old Polish piekło, which arose under the Christian influence (sinners are submerged in boiling tar in hell).