K through 12K through 12 
in the US, the period of schooling from kindergarten through to grade 12 – the final year of high school
in the US, the period of schooling from kindergarten through to grade 12 – the final year of high school- work release
- workroom
- worksheet
- workshop
- work-shy
- workstation
- work-surface
- work-to-rule
- workweek
- world
- World Almanac
- World Bank
- world-beater
- world-beating
- world-class
- WorldCom
- World Council of Churches
- World Cup
- World English
- world-famous
- World Health Organization
- worldliness
- worldly
- worldly-wise
- world music