ar-

Extracted from the word aromatic.

ar-

1. (organic chemistry) Forming classification names for classes of organic compounds that contain a carbon skeleton and one or more aromatic rings.
   • 1900, Edgar Fahs Smith (English translator), R. Anschütz (German editor), Victor von Richter's Organic Chemistry: or, Chemistry of the Carbon Compounds, Third American Edition, Volume II, P. Blakiston's Son & Co., page 393:

     Potassium permanganate oxidizes ac-tetrahydronaphtylamine to o-hydrocinnam-carboxylic acid (p. 245); ar-tetrahydronaphthylamine, however, because of the oxidation of its amided benzene nucleus, is changed to adipic acid together with oxalic acid (B. 22, 767): […]

   • 1919 January 10, C. J. West, abstract of G. Schroeter and K. Thomas, “Transformation of tetrahydronaphthalene (tetralin) in the animal body”; in American Chemical Society, Chemical Abstracts, Volume 13, Number 1, page 43:

     ar-Tetrahydro-α-carbamidonaphthalene, C₁₁H₁₄ON₂, crystallized in square plates from alc., soften at 198° and melts at about 206° (quickly heated, at 212°).

   • 2006, Amit Arora, Aromatic Organic Chemistry, Discovery Publishing House, published 2007, →ISBN, page 173:

     1-Naphthylamine is reduced by sodium and isopentanol to ar-tetrahydro-1-naphthylamine; the prefix ar- is the abbreviation of aromatic and indicates that the four hydrogen atoms are not in the ring containing the amino-group: […]

Shortened from area (because the function describes the area under a hyperbola), by analogy with arc-, the corresponding prefix for the circular trigonometric functions.

ar-

1. (trigonometry) Used to form the names of inverse hyperbolic functions, and the symbols for these functions.

   Synonyms: (sometimes proscribed) arc-, a-, ⁻¹

• [1]
• [2]
• [3]

• 'RA, 'Ra, ra, RA, Ra

ar-

1. prefix for limbs or upright things

From Proto-Celtic *ɸare-. Prefix form of ar (“in front of”).

• (pretonically) IPA^(key): /ar/
• (in stressed syllables) IPA^(key): /œr/

ar-

1. for-, fore-

From Proto-Tocharian *er- (whence also Tocharian B er-), from Proto-Indo-European *h₃er- (“to move, stir”).

ar-

1. to evoke, call up
2. to produce, yield, bring forth

• er- (with i-affection)

From Proto-Brythonic *ar-, from Proto-Celtic *ɸare.^[1]

• IPA^(key): /ar/

ar-

1. on, above, sur-, super-, epi-

   ‎ar- + ‎nofio (“to swim”) → ‎arnofio (“to float”)

   ‎ar- + ‎ysgrif (“writing”) → ‎arysgrif (“inscription, epigraph”)

2. near

   ‎ar- + ‎lliw (“colour”) → ‎arlliw (“shade”)

   ‎ar- + ‎môr (“sea”) → ‎arfor (“coast”)

• R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke et al., editors (1950–present), “ar-”, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies