Dd: dereliction

Don't be a derelict of dialect.

n.

1. Willful neglect, as of duty or principle.

2.

a. The act of abandoning; abandonment.

b. A state of abandonment or neglect.

3. Law

a. A gaining of land by the permanent recession of the water line.

b. The land so gained.

It is a gross dereliction of my duty.
Treasure Island by Stevenson, Robert Louis