at1

[at; unstressed uh t, it] /æt; unstressed ət, ɪt/
preposition
1.
(used to indicate a point or place occupied in space); in, on, or near:
to stand at the door; at the bottom of the barrel.
2.
(used to indicate a location or position, as in time, on a scale, or in order):
at zero; at noon; at age 65; at the end; at the lowest point.
3.
(used to indicate presence or location):
at home; at hand.
4.
(used to indicate amount, degree, or rate):
at great speed; at high altitudes.
5.
(used to indicate a direction, goal, or objective); toward:
Aim at the mark. Look at that.
6.
(used to indicate occupation or involvement):
at work; at play.
7.
(used to indicate a state or condition):
at ease; at peace.
8.
(used to indicate a cause or source):
She was annoyed at his stupidity.
9.
(used to indicate a method or manner):
He spoke at length.
10.
(used to indicate relative quality or value):
at one's best; at cost.
Idioms
11.
be at (someone), to be sexually aggressive toward (a person):
She's pregnant again because he's at her morning, noon, and night.
12.
where it's at, Informal. the place where the most interesting or exciting things happen:
Emma says that Rome is definitely where it's at now.
Origin
before 900; Middle English; Old English æt; cognate with Old Frisian et, Old Norse, Old Saxon, Gothic at, Old High German az, Latin, Old Welsh, Old Breton ad, Greek a- (< a pre-Hellenic IE substratum language), Oscan, Old Irish, Gaulish, Phrygian ad-

at2

[aht, at] /ɑt, æt/
noun
1.
a money of account of Laos, the 100th part of a kip.
Origin
1950-55; < Lao; compare Thai ʔàt formerly, a copper coin worth one eighth of a füang, ultimately < Pali aṭṭha eight

at-

1.
variant of ad- before t: attend.

AT

1.
achievement test.
2.
antitank.

At

1.
ampere-turn.

aT

1.
attotesla.

At

Symbol, Chemistry
1.
astatine.

at.

1.
atmosphere.
2.
atomic.
3.
attorney.

A.T.

1.
Atlantic time.
British Dictionary definitions for at

at1

/æt/
preposition
1.
used to indicate location or position: are they at the table?, staying at a small hotel
2.
towards; in the direction of: looking at television, throwing stones at windows
3.
used to indicate position in time: come at three o'clock
4.
engaged in; in a state of (being): children at play, stand at ease, he is at his most charming today
5.
(in expressions concerned with habitual activity) during the passing of (esp in the phrase at night): he used to work at night
6.
for; in exchange for: it's selling at four pounds
7.
used to indicate the object of an emotion: angry at the driver, shocked at his behaviour
8.
(slang) where it's at, the real place of action
Word Origin
Old English æt; related to Old Norse at to, Latin ad to

at2

/ɑːt; æt/
noun (pl) at
1.
a Laotian monetary unit worth one hundredth of a kip
Word Origin
from Thai

at3

abbreviation
1.
Austria

At

Chemical symbol
1.
astatine
symbol
2.
Also A. ampere-turn

AT

abbreviation
1.
attainment target

at.

abbreviation
1.
Also atm. atmosphere (unit of pressure)
2.
atomic
Word Origin and History for at
prep.

Old English æt, from Proto-Germanic *at (cf. Old Norse, Gothic at, Old Frisian et, Old High German az), from PIE *ad- "to, near, at" (cf. Latin ad "to, toward" Sanskrit adhi "near;" see ad-).

Lost in German and Dutch, which use their equivalent of to; in Scandinavian, however, to has been lost and at fills its place. In choosing between at church, in church, etc. at is properly distinguished from in or on by involving some practical connection; a worshipper is at church; a tourist is in the church.

The colloquial use of at after where ("where it's at") is attested from 1859. At last is recorded from late 13c.; adverbial phrase at least was in use by 1775. At in Middle English was used freely with prepositions (e.g. at after, which is in Shakespeare), but this has faded with the exception of at about, which was used in modern times by Trollope, Virginia Woolfe, D.H. Lawrence, and Evelyn Waugh, but nonetheless is regarded as a sign of incompetent writing by my copy editor bosses.

at-

assimilated form of ad- "to, toward, before" before stems beginning in -t-; see ad-.

at in Medicine

At
The symbol for the element astatine.

at- pref.
Variant of ad-.

at in Science
At  
The symbol for astatine.
astatine
  (ās'tə-tēn')   
Symbol At
A highly unstable, rare, radioactive element that is the heaviest of the halogen elements. Its most stable isotope has a half-life of 8.3 hours. Atomic number 85; melting point 302°C; boiling point 337°C; valence probably 1, 3, 5, 7. See Periodic Table.
at in Technology


IBM PC AT


1. commercial at.
2. The country code for Austria.

Related Abbreviations for at

aT

attotesla

At

  1. ampere-turn
  2. astatine

AT

  1. achievement test
  2. advanced technology
  3. air temperature
  4. antitank
  5. Atlantic Time
  6. automatic transmission

at.

  1. airtight
  2. atmosphere
  3. atomic
  4. attorney
Encyclopedia Article for at

At

radioactive chemical element and the heaviest member of the halogen elements, or Group 17 (Group VIIa) of the periodic table. Astatine, which has no stable isotopes, was first synthetically produced (1940) at the University of California by American physicists Dale R. Corson, Kenneth R. MacKenzie, and Emilio Segre, who bombarded bismuth with accelerated alpha particles (helium nuclei) to yield astatine and neutrons. Naturally occurring astatine isotopes have subsequently been found in minute amounts in the three natural radioactive decay series, in which they occur by minor branching (astatine-218 in the uranium series, astatine-216 in the thorium series, and astatine-215 and astatine-219 in the actinium series). Thirty-three isotopes are known; astatine-210, with a half-life of 8.3 hours, is the longest lived.

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