Out or over there—Somewhere in France.
Parados—The back wall of a trench.
Parapet—The front wall of a trench.
Patrol—One or more men who go out in front and prowl in the dark, seeking information of the enemy.
Periscope—A boxlike arrangement with two mirrors for looking over the top without exposing the napper.
Persuader—A short club with a nail-studded head.
Pip squeak—A German shell which makes that kind of noise when it comes over.
Push up the daisies—To be killed and buried.
Ration party—A party of men which goes to the rear and brings up rations for the front line.
Rest—Relief from trench service. Mostly one works constantly when "resting."