- A felt hat having a tall crown and very wide brim. Also called ten-gallon hat 牛仔帽：一种高顶宽沿的毡帽 也作 ten-gallon hat
- unnilennium
- unnilhexium
- unnilhexiums
- unniloctium
- unnilpentium
- unnilpentiums
- unnilquadium
- unnilquadiums
- unnilquintium
- unnilseptium
- unnoticeable
- unnumbered
- Uno
- unobjectionable
- unobstructed
- unobtrusive
- unoccupied
- unofficial
- unopposed
- unorganized
- unoriginal
- unornament
- unornamented
- unorthodox
- unostentatious