[os] 
[os-uh] . | Anatomy, Zoology. a bone. |
[os] [awr-uh, ohr-uh] . | Anatomy, Zoology. a mouth or orifice of the body. |
[ohs] [oh-sahr] . | Geology. an esker, esp. when of great length. |
| 1. | Old Saxon. |
| 2. | Computers. operating system. |
| Symbol, Chemistry. osmium. |
| (of the calendar) Old Style. |
| 1. | (of the calendar) Old Style. |
| 2. | out of stock. |
| 3. | (in banking) outstanding. |
| 1. | (in prescriptions) the left eye. Origin: < L oculus sinister |
| 2. | Old Saxon. |
| 3. | Old School. |
| 4. | Old series. |
| 5. | (of the calendar) Old Style. |
| 6. | ordinary seaman. |
| 1. | (in prescriptions) the left eye. Origin: < L oculus sinister |
| 2. | ordinary seaman. |
[oh] | 1. | the fifteenth letter of the English alphabet, a vowel. |
| 2. | any spoken sound represented by the letter O or o, as in box, note, short, or love. |
| 3. | something having the shape of an O. |
| 4. | a written or printed representation of the letter O or o. |
| 5. | a device, as a printer's type, for reproducing the letter O or o. |
[oh] interjection, noun, plural O's.| 1. | (used before a name in direct address, esp. in solemn or poetic language, to lend earnestness to an appeal): Hear, O Israel! |
| 2. | (used as an expression of surprise, pain, annoyance, longing, gladness, etc.) |
| 3. | the exclamation “O.” |
| the Saxon dialect of Low German in use before c1100. Abbreviation: OS |
| the collection of software that directs a computer's operations, controlling and scheduling the execution of other programs, and managing storage, input/output, and communication resources. Abbreviation: OS |
| a seaman insufficiently skilled to be classified as an able-bodied seaman. Abbreviation: O.D., O.S., o.s. |
| es·ker (ěs'kər) n. A long, narrow ridge of coarse gravel deposited by a stream flowing in or under a decaying glacial ice sheet. Also called os3. [Irish Gaelic eiscir, from Old Irish escir.] |
| o or O (ō) n. pl. o's or O's also os or Os
|
| old style n.
|
| ordinary seaman n. Abbr. OS A seaman of the lowest grade in the merchant marine. |
| os 1 (ŏs) n. pl. o·ra (ôr'ə, ōr'ə) A mouth or an opening. [Latin ōs, mouth; see ōs- in Indo-European roots.] |
| os 2 (ŏs) n. pl. os·sa (ŏs'ə) A bone. [Latin, bone; see ost- in Indo-European roots.] |
| os 3 (ōs) n. pl. os·ar (ō'sär') See esker. [Swedish ås, ridge, from Old Norse āss.] |
| Os The symbol for the element osmium. |
| OS abbr.
|
| os·mi·um (ŏz'mē-əm) n. Symbol Os A bluish-white, hard metallic element, found in small amounts in osmiridium, nickel, and platinum ores. It is used as a platinum hardener and in making pen points, phonograph needles, and instrument pivots. Atomic number 76; atomic weight 190.2; melting point 3,000°C; boiling point 5,000°C; specific gravity 22.57; valence 2, 3, 4, 8. See Table at element. [From Greek osmē, smell (from the strong odor of osmium tetroxide).] |
O 2
abbr.
oculus
os 1 (ŏs)
n. pl. o·ra (ôr'ə)
An opening into a hollow organ or canal.
The oral cavity; mouth.
os 2 (ŏs)
n. pl. os·sa (ŏs'ə)
Bone.
Os
The symbol for the element osmium.
OS abbr.
Latin oculus sinister (left eye)
| O
The symbol for oxygen. |
| operating system (ŏp'ə-rā'tĭng) Pronunciation Key
Software designed to handle basic elements of computer operation, such as sending instructions to hardware devices like disk drives and computer screens, and allocating system resources such as memory to different software applications being run. Given uniformly designed operating systems that run on many different computers, developers of software do not need to concern themselves with these problems, and are provided with a standard platform for new programs. |
| Os
The symbol for osmium. |
| osmium (ŏz'mē-əm) Pronunciation Key
Symbol Os A hard, brittle, bluish-white metallic element that is the densest naturally occurring element. It is used to make very hard alloys for fountain pen points, electrical contacts, and instrument pivots. Atomic number 76; atomic weight 190.2; melting point 3,000°C; boiling point 5,000°C; specific gravity 22.57; valence 2, 3, 4, 8. See Periodic Table. |
| oxygen (ŏk'sĭ-jən) Pronunciation Key
Symbol O A nonmetallic element that exists in its free form as a colorless, odorless gas and makes up about 21 percent of the Earth's atmosphere. It is the most abundant element in the Earth's crust and occurs in many compounds, including water, carbon dioxide, and iron ore. Oxygen combines with most elements, is required for combustion, and is essential for life in most organisms. Atomic number 8; atomic weight 15.9994; melting point -218.4°C; boiling point -183.0°C; gas density at 0°C 1.429 grams per liter; valence 2. See Periodic Table. Our Living Language : In 1786, the French chemist Antoine Lavoisier coined a term for the element oxygen (oxygène in French). He used Greek words for the coinage: oxy- means "sharp," and -gen means "producing." Oxygen was called the "sharp-producing" element because it was thought to be essential for making acids. Lavoisier also coined the name of the element hydrogen, the "water-producing" element, in 1788. Soon after, in 1791, another French chemist, J. A. Chaptal, introduced the word nitrogen, the "niter-producing" element, referring to its discovery from an analysis of nitric acid. |
OS
1. operating system.
2. [obsolete, ITS], an output spy. See "OS and JEDGAR".
3.
[The Jargon File]
(1997-09-22)
| Os osmium |
OS
|
Os
(Os), chemical element, one of the platinum metals of Group VIIIb of the periodic table and the densest naturally occurring element. A gray-white metal, osmium is very hard, brittle, and difficult to work, even at high temperatures. Of the platinum metals it has the highest melting point, so fusing and casting are difficult. Osmium wires were used for filaments of early incandescent lamps before the introduction of tungsten. It has been used chiefly as a hardener in alloys of the platinum metals, though ruthenium has generally replaced it. A hard alloy of osmium and iridium has been used for tips of fountain pens and phonograph needles, and osmium tetroxide is used in certain organic syntheses.
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