Word.ws English Dictionary

nil per os

nil per os phrase: nothing by mouth: Nothing may be eaten or drunk.

Phrase

nil per os

  1. Nothing by mouth: Nothing may be eaten or drunk.
    • The initial written orders should include: insulin dosage to be administered as soon as the patient appears nil per os, measure all intake and output, and obtain venous blood for measurement of blood or serum urea nitrogen, glucose, acetone [...] and phosphorus.1971, Diabetes Mellitus: Diagnosis and Treatment, volume 3, American Diabetes Association, page 252
    • We evaluated the effect of Colestid on enteral feeding-induced diarrhea in a double-blind placebo-controlled study. Nineteen patients who were nil per os (NPO) for 5 days before initiation of enteral feeding were enrolled in the study and treatment continued for 7 days.1998 June, DeMeo, M et al., “Beneficial effect of a bile acid resin binder on enteral feeding induced diarrhea.”, in The American Journal of Gastroenterology, volume 93, number 6, Elsevier, Abstract
    Synonyms:
    NPO, nil by mouth
    Antonyms:
    per os, PO

Synonyms of nil per os

Antonyms

  • per os
  • PO

Origin of nil per os

From Latin nīl (“nothing”) + per (“by means of”) + ōs (“mouth”), literally “nothing by mouth”.

Questions about nil per os

What does nil per os mean?
Nil per os means nothing by mouth: Nothing may be eaten or drunk.
What part of speech is nil per os?
Nil per os is a phrase.

Words near nil per os in the dictionary

  1. Nikšić
  2. nil
  3. nil by mouth
  4. nil desperandum
  5. nil disease
  6. nil per os
  7. nil-
  8. Nila
  9. nilable
  10. Niladevi
  11. niladic

Source and license

Adapted from Wiktionary: nil per os (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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