twine around - ungraded
- tyro
- Tyrol
- Tyrolean
- Tyrone
- Tyrrhene
- Tyrrhenian
- Tyrrhenian Sea
- tzar
- Tzigane
- u . U - uncle
- U-boat
- U-turn
- U.
- u.c. upper case
- U.D.C. Universal Decimal Classification
- U.K. United Kingdom of Great Britain and Northern Ireland
- U.S.P. United States Pharmacopoeia
- U.S.S.R. Union of Soviet Socialist Republics
- UAR United Arab Republic
- ubiety
- ubiquitous
- ubiquity
- UCB University of California at Berkeley
- UCD University of California at Davis
- UCLA University of California at Los Angeles
- UCSB University of California at Santa Barbara
- UCSD University of California at San Diego
- UCSF University of California at San Francisco
- udder
- udometer
- UDP User Data Protocol
- UFO unidentified flying object
- Uganda
- Ugandan
- ugh
- uglify
- ugliness
- ugly
- ugly as a scarecrow
- ugly as sin