| an arrangement of five objects, as trees, in a square or rectangle, one at each corner and one in the middle. |
| a scrap or morsel of food left at a meal. |
| U1 | |
| —symbol for | |
| 1. | united |
| 2. | unionist |
| 3. | university |
| 4. | in Britain |
| a. universal (used to describe a category of film certified as suitable for viewing by anyone) | |
| b. (as modifier): a U film | |
| 5. | chem uranium |
| 6. | biochem uracil |
| —abbreviation for | |
| 7. | text messaging you |
| —adj | |
| 8. | old-fashioned, informal (Brit) Compare non-U (esp of language habits) characteristic of or appropriate to the upper class |
| U. | |
| —abbreviation for | |
| 1. | maths union |
| 2. | unit |
| 3. | united |
| 4. | university |
| 5. | upper |
U 3
The symbol for the element uranium.
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uranium (y -rā'nē-əm) Pronunciation Key
Symbol U A heavy, silvery-white, highly toxic, radioactive metallic element of the actinide series. It has 14 known isotopes, of which U 238 is the most naturally abundant, occurring in several minerals. Fissionable isotopes, especially U 235, are used in nuclear reactors and nuclear weapons. Atomic number 92; atomic weight 238.03; melting point 1,132°C; boiling point 3,818°C; specific gravity 18.95; valence 2, 3, 4, 5, 6. See Periodic Table. |
| u up quark |
U
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u.
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U.
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