- worm gears - mathematical models
- worm teeth
- Woven fabrics of cotton
- wringing the pulp
- Wydawnictwa ilustrowane
- X-ray
- X-ray crystallography
- Xenobiotics
- Xerography
- xylenes - derivatives
- xylylene polymers
- YAG lasers
- yeast
- yeast - construction
- yeast - fermentation factor
- yeast - properties
- youth unemployment
- Z transformation - Tasks and Exercices
- Zeolites
- Zeolith
- Zintl compounds
- Zirconium - Metallurgy
