Science Words That Start With U: Key Terms and Definitions

In this article, you will discover a comprehensive list of science-related words starting with the letter “U.

  1. Ultraviolet- Electromagnetic radiation with a wavelength shorter than that of visible light.
  2. Ultrasound- Sound waves with frequencies higher than the audible limit for humans.
  3. Uranium- A heavy, radioactive metallic element used as fuel in nuclear reactors.
  4. Ubiquitin- A small protein that regulates protein degradation in cells.
  5. Ultracentrifuge- A high-speed centrifuge used to separate particles based on density.
  6. Uncertainty- The estimated amount by which a measured or calculated value may deviate.
  7. Upwelling- The rising of seawater, magma, or other liquid.
  8. Urea- A waste product formed in the liver, filtered from the blood by the kidneys.
  9. Urography- Radiographic examination of the urinary tract.
  10. Umbra- The fully shaded inner region of a shadow cast by an opaque object.
  11. Ultrafine- Extremely small particles on a nanometer scale.
  12. Ultrasonic- Sound frequencies above 20,000 hertz, beyond human hearing.
  13. Ultranationalism- Extreme devotion to one’s nation.
  14. Ultrastructure- Fine details of a cell structure observable by electron microscopy.
  15. Unicellular- Organisms consisting of a single cell.
  16. Uniformitarianism- The principle that geological processes occurring now are the same as those in the past.
  17. Universalism- The belief that some ideas or concepts have universal application.
  18. Urinalysis- A test of urine for diagnostic purposes.
  19. Ultrafast- Occurring at extremely fast timescales, often in femtoseconds or picoseconds.
  20. Uropod- A part of the tail appendage in some crustaceans.
  21. Uropathy- Any disease or disorder of the urinary system.
  22. Ureter- The duct by which urine passes from the kidney to the bladder.
  23. Uterus- The organ in a female mammal where offspring are conceived and gestate.
  24. Ultramafic- Igneous rocks containing magnesium and iron.
  25. Unimolecular- Consisting of or involving a single molecule.
  26. Unidirectional- Operating or moving in a single direction.
  27. Ultranational- Relating to extreme devotion to one’s nation.
  28. Uterton- Seismic wave propagating in the Earth’s crust.
  29. Ubiquitous- Found everywhere, especially at the cellular level.
  30. Uranography- The branch of astronomy dealing with the mapping of stars and planets.
  31. Urinalysis- The analysis of urine samples for medical diagnosis.
  32. Unipotent- Cells capable of developing into only one cell type.
  33. Urokinase- An enzyme that promotes the breakdown of blood clots.
  34. Umbonate- Having a knob-like structure, especially in biology.
  35. Urticaria- The medical term for hives or nettle-rash.
  36. Ulceration- The formation of an ulcer.
  37. Ultrastable- Extremely resistant to change or decomposition.
  38. Undulator- A device that produces a periodic magnetic field to make synchrotron radiation.
  39. Urea cycle- The series of biochemical reactions in the body that produces urea.
  40. Ultrafiltration- A filtration process using fine membranes.
  41. Urinoscopy- Examination of urine for diagnostic purposes.
  42. Uranide- Elements analogous to uranium in their chemical behavior.
  43. Uniaxial- Having a single axis of symmetry.
  44. Underwater- Located, found, or occurring beneath the surface of the water.
  45. Ultraprecision- Involving extremely high precision and accuracy.
  46. Uranology- The study of the heavens and celestial bodies.
  47. Urodynamic- The study of the functional processes of the urinary tract.
  48. Uranotherapy- Medical treatment using uranium compounds.
  49. Urethritis- Inflammation of the urethra.
  50. Ultraheat- To heat something to an extremely high temperature.
  51. Ultramicroscopy- Methods to view objects smaller than the wavelength of visible light.
  52. Uranometry- The measurement of the positions and characteristics of celestial bodies.
  53. Univalent- Having a valence of one.
  54. Ultraphosphate- Highly phosphated compound or substance.
  55. Uroflowmetry- A test measuring the flow rate of urine.
  56. Universal- Applicable everywhere or in all cases.
  57. Urobilin- A bile pigment excreted in urine.
  58. Ultracytochemical- Relating to the chemical study of cells at high magnification.
  59. Urinalization- The formation or conversion into urine.
  60. Upconversion- A process converting lower frequency photons to higher frequency photons.
  61. Urticant- Substance causing itching or blistering.
  62. Ureotelic- Organisms that excrete excess nitrogen as urea.
  63. Ultrapedestrian- Extremely lightweight and designed for mobility.
  64. Uracil- A nitrogenous base found in RNA.
  65. Unilamellar- Composed of a single layer, commonly in a molecular context.
  66. Ultrastructural- Pertaining to the fine structure of a biological specimen.
  67. Urinometer- Device used to measure the specific gravity of urine.
  68. Ultranationalistic- Excessively nationalistic or patriotic.
  69. Ultratough- Extremely strong and durable under stress or pressure.
  70. Uroplakin- A protein associated with the urothelial surface.
  71. Uniparous- Producing a single offspring at a time.
  72. Ultraquiet- Exceptionally silent, often referring to equipment or environments.
  73. Ureteroscopy- A procedure for examining the upper urinary tract.
  74. Ultradense- Extremely dense or compact in structure.
  75. Upquark- A type of elementary particle in the quark family.
  76. Uniform- Consistent and unchanging nature.
  77. Ultraexpensive- Exceptionally expensive.
  78. Uridine- A nucleoside component of RNA.
  79. Unpalatable- Not pleasant to taste.
  80. Ultraperipheral- Existing at the extreme outer boundary or limit.
  81. Uptake- The absorption or intake of substances.
  82. Uranogeology- The study of the geological aspects of uranium.
  83. Urolithiasis- The formation of stones in the urinary system.
  84. Ultrafast laser- A laser that emits extremely short pulses, typically in the femtosecond to picosecond range.
  85. Urgent- Requiring immediate action or attention.
  86. Ultramicrotome- A device used to cut extremely thin slices of material for microscopy.
  87. Ultrasonication- The process of using ultrasound to agitate particles or substances.
  88. Unicuspate- Having a single cusp or point.
  89. Ursids- A family of mammals including bears.
  90. Unpolarized- Not having a fixed direction of oscillation.
  91. Ultraleft- Of or pertaining to radical left-wing politics.
  92. Ultrathin- Extremely thin, often on a nanometer scale.
  93. Uropoiesis- The production and excretion of urine.
  94. Uvulitis- Inflammation of the uvula.
  95. Urodelan- Of or relating to the order Urodela, comprising newts and salamanders.
  96. Ultrabaric- Pertaining to very high pressure.
  97. Upwarp- A type of geological uplift.