| twenty- first century(expression, adjective, idiom, current, stylish) |
| twenty-first century(expression, adjective, radical, progressive, in) |
| ultramodern(adjective, unusual, strange, fresh, original) |
| unaccustomed(adjective, unusual, strange, fresh, original) |
| uncontaminated(adjective, unusual, strange, fresh, original) |
| unfamiliar(adjective, unusual, strange, fresh, original) |
| unknown(adjective, unusual, strange, fresh, original) |
| unlike(adjective, unusual, strange, fresh, original) |
| unseasoned(adjective, unusual, strange, fresh, original) |
| unskilled(adjective, unusual, strange, fresh, original) |
| unspoiled(adjective, unusual, strange, fresh, original) |
| untouched(adjective, unusual, strange, fresh, original) |
| untrained(adjective, unusual, strange, fresh, original) |
| untried(adjective, unusual, strange, fresh, original) |
| untrodden(adjective, unusual, strange, fresh, original) |
| unused(adjective, unusual, strange, fresh, original) |
| unusual(adjective, strange, fresh, original, current) |
| up-to-the-minute(adjective, current, modern, radical, up-to-date) |
| widespread(adjective, present, modern, general, prevailing) |
| youthful(adjective, unusual, strange, fresh, original) |