Venal means open to bribery or corrupt — a venal official. Venial means minor and easily forgiven — a venial fault. They differ by one letter and are close to opposites in severity: one is a serious accusation, the other an excuse.
The core difference
Corruption and forgivability, one letter apart.
- venal — corrupt, bribable: venal politicians.
- venial — minor, forgivable: a venial offence.
The theological origin
Venial comes from Catholic theology, where a venial sin is a lesser one, as against a mortal sin. That is where its sense of forgivability comes from, and the pairing with mortal is worth knowing because it fixes the severity.
The roots
Venal is from Latin venum, sale — something available for purchase, hence a person who can be bought. Venial is from venia, forgiveness. Different roots that landed a letter apart.