The word "venial" means a minor or forgivable mistake or offense. It refers to a wrongdoing that is not considered very serious and can be easily forgiven. Full definition
After the customary «Bless me Father, for I have sinned», the programme instructs the user to tap in the number of days since last confession, the number of venial versus mortal sins (selected from a list of the seven deadly sins and the ten commandments) and then further details of each sin. (newscientist.com)
Scobie is not satisfied with the distinction between venial and mortal sin; he needs to weigh one mortal sin against another as if to chart the available degrees of damnation. (firstthings.com)
Purgatory does not cleanse mortal sin from the soul only venial sin. (religion.blogs.cnn.com)