From treat + -ment.

• IPA: /ˈtɹiːtmənt/

treatment

1. The process or manner of treating someone or something.

   He still has nightmares resulting from the abusive treatment he received from his captors.

2. Medical care for an illness or injury.

   A treatment or cure is applied after a medical problem has already started.

   Cancer survivors who got radiation treatments as children have nearly twice the risk of developing diabetes as adults.

   The change is due largely to the increased availability of antiretroviral treatment.

3. The use of a substance or process to preserve or give particular properties to something.
4. (countable) A treatise; a formal written description or characterization of a subject.
   • 1992, Rudolf M[athias] Schuster, The Hepaticae and Anthocerotae of North America: East of the Hundredth Meridian, volume V, Chicago, Ill.: Field Museum of Natural History, →ISBN, page vii:

     Firstly, I continue to base most species treatments on personally collected material, rather than on herbarium plants.

5. (countable, film) A brief, third-person, present-tense summary of a proposed film.
6. (obsolete) entertainment; treat
   • 1725–1726, Homer, “Book 14”, in [William Broome, Elijah Fenton, and Alexander Pope], transl., The Odyssey of Homer. […], London: […] Bernard Lintot, →OCLC ↗:

     Accept such treatment as a swain affords.

• treat

• French: traitement
• German: Behandeln, Behandlung, Umgang
• Italian: trattamento
• Portuguese: tratamento
• Russian: обраще́ние
• Spanish: trato

• French: traitement
• German: Behandlung
• Italian: trattamento, cura
• Portuguese: tratamento
• Russian: лече́ние
• Spanish: tratamiento

• French: traitement
• German: Behandlung
• Italian: trattamento
• Portuguese: tratamento
• Spanish: tratamiento