World War II "X" Words: X-Rays, X-Craft, XLR-04, and More

Words starting with X are rare in WWII vocabulary, but a few notable ones exist:

1. X-ray

Ubiquitous in military medicine: field hospitals, TB screening, shrapnel location. Mobile units followed front lines.

2. X-Craft (X-Class Submarines)

British 4-man midget subs (27 tons). Famous for Operation Source (Sept 1943) — attacked Tirpitz in Norwegian fjord. Also recon, beach survey for D-Day.

3. XLR-04 Rocket Engine

Experimental liquid-fueled engine (Reaction Motors) for assisted-takeoff (JATO) and early missile research. Precursor to XLR-11 (X-1 rocket plane).

4. XM1 Garand Prototype

Early test iteration of the M1 Garand (standard US rifle). "XM" = experimental model. Not issued.

5. Xerography (Not "Xerox" Yet)

Chester Carlson's electrostatic copying (patented 1942). First commercial Xerox 914 arrived 1959. Wartime use: limited lab reproduction of maps/documents.

Bonus: "X" as Designator

• X-Planes (X-1, X-2...) — post-war, but roots in WWII rocket research.
• X-Day / X-Hour — generic operation start variables.

Scrabble value: high. Historical weight: niche but real.