uuuu
Definition(s) of “U”
u
abbreviation Physics
denoting quantum states or wave functions that change sign on inversion through the origin. The opposite of g . [ORIGIN: from German ungerade ‘odd.’ ]
symbol [in combination ]
(in units of measurement) micro- (10 −6): : direct readout of concentration in ug or mg/l.
ORIGIN substituted for mu (μ).
U 1 |yoō| (also u)
noun ( pl. Us or U's )
1 the twenty-first letter of the alphabet.
• denoting the next after T in a set of items, categories, etc.
2 ( U) a shape like that of a capital U, esp. a cross section : [in combination ] U-shaped glaciated valleys.
U 2
symbol
the chemical element uranium.
U 3
adjective informal chiefly Brit.
(of language or social behavior) characteristic of or appropriate to the upper social classes : U manners.
ORIGIN abbreviation of upper class ; coined in 1954 by Alan S. C. Ross, professor of linguistics, the term was popularized by its use in Nancy Mitford's Noblesse Oblige (1956).
U 4 |oō|
noun
a Burmese title of respect before a man's name, equivalent to Mr. : U Thien San.
uranium |yoŏˈrānēəm|
noun
the chemical element of atomic number 92, a gray, dense radioactive metal used as a fuel in nuclear reactors. (Symbol: U)
Uranium is a chemically reactive metal belonging to the actinide series. Becquerel discovered radioactivity in uranium in 1896, and its capacity to undergo fission led to its use as a source of energy, though the fissile isotope, uranium-235, has to be separated from the more common uranium-238 before it can be used in nuclear weapons. The atom bomb exploded over Hiroshima in 1945 contained uranium-235.
ORIGIN late 18th cent.: modern Latin, from Uranus + -ium .