There are 13 10-letter words that start with 'was'.
| washateria | washbasins | washboards |
| washcloths | washeteria | washhouses |
| washstands | wassailers | wassailing |
| wastefully | wastelands | wastepaper |
| wastewater | ||
Note: These 13 10-letter words that start with 'was' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with wash, wast, wasp, wass, wasa.
4-letter words start with 'was' (3)