66ed

Welsh

Welsh numbers (edit)
 ←  65 66 67  → 
    Cardinal (vigesimal): trigain ac chwech, (before nouns) trigain ac chwe
    Cardinal (decimal): chwe deg chwech, (before nouns) chwe deg chwe
    Ordinal: trigain ac chweched
    Ordinal abbreviation: 66ed

Adjective

66ed

  1. abbreviation of trigain a chweched: 66th