See also: pos, Pos, Pos., POs, pos-, pós, pós-, pòs, pôs, pōš, and pøs



  • (file)


POS (countable and uncountable, plural POSes)

  1. (law) Initialism of proof of service.
  2. (medicine) Initialism of peripheral oxygen saturation.
  3. (linguistics) Initialism of part of speech.
    • 2018, Clarence Green; James Lambert, “Advancing disciplinary literacy through English for academic purposes: Discipline-specific wordlists, collocations and word families for eight secondary subjects”, in Journal of English for Academic Purposes, volume 35, DOI:, page 109:
      To include part-of-speech (POS) information, the corpus was tagged using the CLAWS tagger.
  4. (retail) Initialism of point of sale or point of service.
  5. (computing) Initialism of proprietary operating system.
  6. (navigation, aviation) Initialism of position and orientation system.
  7. (vulgar, of a person or thing) Initialism of piece of shit.
    • 2014, Harmony Rose, Married Under the Influence: A True Story, Bloomington, IN: Archway Publishing, →ISBN, page 78:
      I told him he is a POS for saying that to me (what a terrible thing to say to my husband! I am just as guilty sometimes for saying hurtful things), and how dare he try and hurt me in such a cruel way, telling me he hates me and wishing he could tell me he was unfaithful!



  1. (Internet, text messaging) Initialism of parent over shoulder (i.e. observing the young user's conversation) (Can we add an example for this sense?)