This list contains acronyms, initialisms, and pseudo-blends  that begin with the letter U.

For the purposes of this list:

  • acronym = an abbreviation pronounced as if it were a word, e.g., SARS = severe acute respiratory syndrome, pronounced to rhyme with cars
  • initialism = an abbreviation pronounced wholly or partly using the names of its constituent letters, e.g., CD = compact disc, pronounced cee dee
  • pseudo-blend = an abbreviation whose extra or omitted letters mean that it cannot stand as a true acronym, initialism, or portmanteau (a word formed by combining two or more words).
(a) = acronym, e.g.: SARS – (a) severe acute respiratory syndrome
(i) = initialism, e.g.: CD – (i) compact disc
(p) = pseudo-blend, e.g.: UNIFEM – (p) United Nations Development Fund for Women
(s) = symbol (none of the above, representing and pronounced as something else; for example: MHz – megahertz)

Some terms are spoken as either acronym or initialism, e.g., VoIP, pronounced both as voyp and V-O-I-P.

(Main list of acronyms)

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UD edit

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UJ edit

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  • UL – (i) Underwriters Laboratories
  • ULEB – (a) Union des ligues européens de basket-ball, French for "Union of European Basketball Leagues"
  • ULF – (i) Ultra Low Frequency
  • ULOF – unprotected loss of flow (nuclear accident)
  • ULOHS – unprotected loss of heat sink (nuclear accident)
  • UTOP – unprotected transient overpower (nuclear accident)

UM edit

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UZ edit