| 1. | payroll. |
| 2. | percentile rank. |
| 3. | public relations. |
| 4. | Slang: Often Disparaging and Offensive. Puerto Rican. |
| 5. | Puerto Rico (approved esp. for use with zip code). |
| praseodymium. |
| 1. | parliamentary report. |
| 2. | Roman people. Origin: < L populus Rōmānus  |
| 3. | press release. |
| 4. | prize ring. |
| 5. | proportional representation. |
| 6. | public relations. |
| 7. | Puerto Rico. |
| public relations. |
| Pr 1 The symbol for the element praseodymium. |
| Pr 2 abbr.
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| PR abbr.
|
pra·se·o·dym·i·um  (prā'zē-ō-dĭm'ē-əm, prā'sē-)  n. Symbol Pr A soft, silvery, malleable, ductile rare-earth element that develops a characteristic green tarnish in air. It occurs naturally with other rare earths in monazite and is used to color glass and ceramics yellow, as a core material for carbon arcs, and in metallic alloys. Atomic number 59; atomic weight 140.908; melting point 935°C; boiling point 3,127°C; specific gravity 6.8; valence 3, 4. See Table at element. [New Latin, from German Praseodym : Greek praseos, variant of prasios, leek-green (from prason, leek) + (di)dymium.] |
| prov·erb (prŏv'ûrb') n.
[Middle English proverbe, from Old French, from Latin prōverbium : prō-, forth; see pro-1 + verbum, word; see wer-5 in Indo-European roots.] |
| public relations pl.n. Abbr. PR
|
| Puer·to Ri·co (pwěr'tə rē'kō, pôrt'ə, pōrt'ə, pwěr'tō) Abbr. PR or P.R. A self-governing island commonwealth of the United States in the Caribbean Sea east of Hispaniola. Inhabited by Tainos when it was discovered by Columbus in 1493, it was colonized by the Spanish in the 16th century and ceded to the United States in 1898 after the Spanish-American War. Puerto Ricans were granted U.S. citizenship in 1917, although residents of the island do not vote in U.S. presidential elections. Commonwealth status was proclaimed in 1952 and has been upheld by various plebiscites since the 1960s. San Juan is the capital and the largest city. Population: 3,940,000. Puer'to Ri'can adj. & n. |
Pr
Pr 1
The symbol for the element praseodymium.
PR
Packet Radio
pr networking
The country code for Puerto Rico.
(1999-01-27)
| pr preferences |
Pr
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PR
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Pr
((Pr), chemical element, rare-earth metal of transition Group IIIb of the periodic table, used as the element in special alloys and, as its oxide, in glasses. Moderately soft, ductile, and malleable, this silvery metal rapidly displaces hydrogen from water and slowly reacts in air, developing a green oxide coating, which chips. For preservation, the metal must be sealed in a plastic covering or kept in mineral oil. Praseodymium was discovered in didymia, a mixture of several rare-earth oxides. From it, by repeated fractional crystallization of ammonium didymium nitrate, Carl Auer von Welsbach separated (1885) salts of the elements praseodymium (the green fraction) and neodymium. Praseodymium occurs in minerals such as monazite and bastnaesite and as one of the products of nuclear fission. Natural praseodymium is all stable isotope praseodymium-141. This element is commercially separated and purified by ion-exchange techniques; the reduction of the fluoride or chloride with calcium is one way in which the metal itself is prepared
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