English Words Starting With I

• isoamyl group

  nounC2
  /ˌaɪ.səʊˈæ.mɪl ɡruːp/A specific branched-chain alkyl group in organic chemistry with the formula (CH₃)₂CHCH₂CH₂–, derived from isoamyl alcohol.
• isoamyl salicylate

  nounVery Low
  /ˌaɪsəʊˌæmɪl səˈlɪsɪleɪt/A synthetic ester used as a fragrance agent and flavoring compound, known for its characteristic floral, sweet aroma reminiscent of orchids or wintergreen.
• isoantibody

  nounRare (Highly Technical)
  /ˌaɪ.səʊˈæn.tɪˌbɒd.i/An antibody produced in response to, and capable of reacting against, antigens from another individual of the same species.
• isoantigen

  nounC2 (Very low frequency, specialised)
  /ˌaɪ.səʊˈæn.tɪ.dʒən/A substance, such as a protein or polysaccharide, that acts as an antigen in individuals of a different genetic background (i.e., within the same species).
• isobar

  nounC2
  /ˈaɪ.səʊ.bɑː/A line on a weather map connecting points with equal atmospheric pressure.
• isobaric spin

  nounC2
  /ˌaɪsə(ʊ)ˈbarɪk ˈspɪn/A quantum number used in nuclear and particle physics to differentiate between particles that are identical except for their electric charge; also called isotopic spin or I-spin.
• isobath

  nounC1
  /ˈaɪ.səʊ.bæθ/a line on a map joining points of equal depth below the surface of a body of water (sea, lake).
• isobathytherm

  nounExtremely low
  /ˌaɪsəʊˈbæθɪθɜːm/A line on a map or chart connecting points of equal temperature at the same depth in a body of water, typically the ocean.
• isobront

  nounVery Rare
  /ˈaɪ.sə(ʊ)ˌbrɒnt/A line on a map connecting points at which a thunderstorm began simultaneously.
• isobutane

  nounC2+
  /ˌaɪsəʊˈbjuːteɪn/A colourless, flammable hydrocarbon gas (C₄H₁₀) with a branched-chain structure, used mainly as a refrigerant and propellant.
• isobutyl nitrite

  nounVery Low
  /ˌaɪsə(ʊ)ˈbjuːtɪl ˈnaɪtraɪt/A chemical compound with the formula (CH₃)₂CHCH₂ONO, used primarily as a recreational drug (popper) that produces vasodilation and euphoria.
• isobutyl propionate

  nounVery Low
  /ˌaɪsəʊˌbjuːtɪl ˈprəʊpiəneɪt/A colorless liquid ester with a fruity odor, used as a flavoring agent and in perfumes.
• isobutylene

  nounVery Low
  /ˌaɪ.səʊˈbjuː.tɪ.liːn/A flammable, volatile hydrocarbon (C₄H₈) with a double bond, used as a chemical intermediate.
• isocarboxazid

  nounC2
  /ˌaɪsəʊkɑːˈbɒksəzɪd/A specific hydrazine-derived monoamine oxidase inhibitor (MAOI) drug, formerly used as an antidepressant.
• isochasm

  nounVery Low
  /ˈaɪ.sə(ʊ)ˌkæz.əm/A line on a map connecting points that have equal frequency of auroral displays.
• isocheim

  nounVery Rare
  /ˈaɪsə(ʊ)kaɪm/A line on a map connecting points with the same average winter temperature.
• isochor

  nounRare
  /ˈaɪsə(ʊ)kɔː/A line on a graph representing a process during which the volume of a system remains constant.
• isochore

  nounLow (C2)
  /ˈaɪ.səʊ.kɔː/In molecular biology and genetics: A region of DNA with a relatively constant guanine-cytosine (GC) content and base composition. In physics: A line on a graph representing changes in a system at constant volume.
• isochron

  nounVery low
  /ˈaɪ.səʊ.krɒn/A line on a map or graph connecting points of equal time.
• isochrone

  nounC2
  /ˈaɪ.sə(ʊ).krəʊn/A line on a map connecting points where something occurs or arrives at the same time.

Showing 3301–3320 of 3621 words.