American English to British English: Letter U
U.K. UK
U.S.A. US
Ultralight (aircraft) Microlight (aircraft)
Undecillion AE n+36 zeros Undecillion BE n+66 zeros
undershirt Singlet
Unemployed Redundant
Ungradable Ungradeable
Unionize Unionise
Unlisted number Ex-directory
Unparalleled Unparallelled
Unrivaled Unrivalled
Unrivaling Unrivalling
Upstairs Above stairs
Upward Upwards
Urbanization Urbanisation
Urbanize Urbanise
Usability Useability
Usable Useable
Utilize Utilise
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