Green’s Dictionary of Slang

1. a grave; thus (WWI milit.) become a landowner, to die.

1890–1904		Farmer & Henley Sl. and Its Analogues.
1937–84		Partridge DSUE (1984) 664/2: landowner, become a, to die: late C.19–20, esp. among soldiers in WW1.

2. dirt beneath the fingernails.

1890–1904

Farmer & Henley Sl. and Its Analogues.