English Words Starting With U

• unburden

  verbverb-transitiveC1
  /ʌnˈbɜːdn/To relieve (someone or oneself) of a burden, worry, or secret.
• unbutton

  verbverb-intransitiveverb-transitiveB2
  /ʌnˈbʌt(ə)n/To undo the buttons of a garment.
• uncage

  verb-transitiveC2
  /ʌnˈkeɪdʒ/To release from a cage or confinement; to set free.
• uncanny valley

  nounC2
  /ʌnˈkæni ˈvæli/A concept in robotics and computer graphics describing the point at which a humanoid object (robot, CGI character) appears almost, but not perfectly, human, causing a strong sense of unease, eeriness, or revulsion in the observer.
• uncap

  verbverb-intransitiveverb-transitiveLow
  /ʌnˈkap/To remove a cap or cover from something.
• uncas

  nounVery Low (C2+)
  /ˈʌŋkəs/A borrowing from various First Nations/Native American languages (e.g., Mohegan-Pequot), often used in historical or literary contexts, most famously as the name of a prominent 17th-century Mohegan sachem (leader). It is not a standard English word with a lexical definition.
• uncase

  verb-transitiveRare
  /ʌnˈkeɪs/To remove something from a case or covering.
• uncertainty

  nounHigh
  /ʌnˈsɜːt(ə)nti/The state of being unsure, not known, or not definite; a lack of certainty.
• uncertainty principle

  nounC2
  /ʌnˈsɜːtnti ˈprɪnsɪpl/A fundamental concept in quantum mechanics stating that it is impossible to simultaneously know both the exact position and exact momentum of a particle.
• unchain

  verbverb-transitiveLow to Medium
  /ʌnˈtʃeɪn/To release or free from chains, shackles, or restraints.
• uncharge

  verb-transitiveC1/C2 (Low frequency, technical/legal)
  /ʌnˈtʃɑːdʒ/To remove an electrical charge; to formally withdraw an accusation or criminal charge.
• uncharted territory

  nounC1
  /ʌnˈtʃɑːtɪd ˈtɛrɪtri/A situation, experience, or area of study that is completely new, unknown, and not previously explored or mapped.
• unchoke

  verb-transitiveLow (Technical/Literary)
  /ʌnˈtʃəʊk/To remove an obstruction from something; to free from a state of being choked or blocked.
• unchurch

  verbverb-transitiveC2 (Proficient User/Very Low Frequency)
  /ʌnˈtʃɜːtʃ/To expel or exclude from membership in a church or religious body; to deprive of ecclesiastical character, rights, or status.
• uncia

  nounVery Low (Technical/Historical)
  /ˈʌnsɪə/A historical unit of measurement, specifically one twelfth of a Roman pound (approximately 27.3 grams) or one twelfth of a Roman foot (uncia).
• uncial

  adjectivenounC2
  /ˈʌnsɪəl/A style of large, rounded handwriting used in ancient and medieval manuscripts, particularly between the 4th and 8th centuries.
• unciform

  adjectivenounC2
  /ˈʌnsɪfɔːm/Having the shape of a hook; hook-shaped.
• uncinariasis

  nounVery Low
  /ˌʌnsɪnəˈraɪəsɪs/A parasitic infection caused by hookworms of the genus Necator or Ancylostoma.
• uncinate process

  nounRare
  /ˈʌnsɪnət ˈprəʊsɛs/A slender, hook-shaped or curved bony or cartilaginous projection.
• uncinus

  nounVery low
  /ʌnˈsʌɪnəs/A specific type of cloud formation, or a hooked anatomical structure.

Showing 281–300 of 1514 words.